Arginine • Squalane • Piper methysticum root extract • Capsicum annuum fruit extract • Cassia Cinnamon bark extract • Triticum vulgare germ Oil (wheat) • Panax ginseng root extract • Vitex Agnus Castus berry extract • Zingiber officinale root extract • Eleutherococcus senticosus root extract • Eurycoma Longifolia Jack root extract • Withania somnifera root extract • Tribulus terrestris fruit extract • Epimedium sagittatum leaf, stem extract. Other Ingredients: Water, Alcohol, PEG-12 Glyceryl Dimyristate, Phenoxyethanol, Carbomer, Polysorbate 60, Sorbitan Stearate, Glyceryl Stearate, PEG-100 STEARATE, Caprylyl Glycol, Ethylhexylglycerin, Hexylene Glycol, Disodium EDTA, Potassium Sorbate.
Brand name products often contain multiple ingredients. To read detailed information about each ingredient, click on the link for the individual ingredient shown above.
Below is general information about the effectiveness of the known ingredients contained in the product HighTest for Men HardKnight Testoster-1 Virility Intensifying Gel. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product HighTest for Men HardKnight Testoster-1 Virility Intensifying Gel. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
POSSIBLY SAFE ...when used orally and appropriately, short-term. Ashwagandha has been used with apparent safety in doses of up to 1250 mg daily for up to 6 months (3710,11301,19271,90649,90652,90653,97292,101816,102682,102683) (102684,102685,102687,103476,105824,109586,109588,109589,109590). ...when used topically. Ashwagandha lotion has been used with apparent safety in concentrations up to 8% for up to 2 months (111538).
PREGNANCY: LIKELY UNSAFE
when used orally.
Ashwagandha has abortifacient effects (12).
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally in amounts typically found in food. Capsicum has Generally Recognized as Safe (GRAS) status in the US (4912). ...when used topically and appropriately (7038,10650,105345). The active capsicum constituent capsaicin is an FDA-approved ingredient used in certain over-the-counter, topical preparations (272).
POSSIBLY SAFE ...when used orally and appropriately, short-term in medicinal amounts. A specific sustained-release chili extract (Capsifen) has been used safely in doses of up to 200 mg daily, for up to 28 days (105196). ...when used intranasally and appropriately, short-term. Capsicum-containing nasal sprays, suspensions, and swabs seem to be safe when applied multiple times over 24 hours or when applied daily or every other day for up to 14 days. Although no serious side effects have been reported in clinical trials, intranasal application of capsicum-containing products can be very painful (14322,14324,14328,14329,14351,14352,14353,14356,14357) (14358,14359,14360,15016,105204). POSSIBLY UNSAFE when used orally, long-term or in high doses. There is concern that long-term use or use of excessive doses might be linked to hepatic or kidney damage, as well as hypertensive crisis (12404,40569,40606). There is insufficient reliable information available about the safety of capsicum when injected.
CHILDREN: POSSIBLY UNSAFE
when used topically in children under 2 years old (272).
There is insufficient reliable information available about the safety of capsicum when used orally in children.
PREGNANCY: LIKELY SAFE
when used topically and appropriately (272).
PREGNANCY: POSSIBLY SAFE
when used orally and appropriately, short-term.
Capsicum 5 mg daily has been used for up to 28 days during the latter half of the second trimester and the third trimester (96457).
LACTATION: LIKELY SAFE
when used topically and appropriately (272).
LACTATION: POSSIBLY UNSAFE
when used orally.
Dermatitis can sometimes occur in infants when foods heavily spiced with capsicum peppers are ingested during lactation (739). Also, observational research suggests that intake of raw capsicum peppers during pregnancy is associated with an increased risk of sensitization to inhalant allergens in children by the age of 2 years (41021).
LIKELY SAFE ...when consumed in amounts commonly found in foods. Cassia cinnamon has Generally Recognized As Safe (GRAS) status in the US for use as a spice or flavoring agent (4912) ...when used orally and appropriately, short-term. Cassia cinnamon 1-2 grams daily has been used safely for up to 3 months (17011,21914). Cassia cinnamon 3-6 grams daily has been used safely for up to 6 weeks (11347,14344). Cassia cinnamon extract corresponding to 3 grams daily of cassia cinnamon powder has also been used safely for up to 4 months (21916).
POSSIBLY SAFE ...when used topically, short-term. Cassia cinnamon oil 5% cream applied topically to the legs has been used safely in one clinical trial (59580).
POSSIBLY UNSAFE ...when used orally in high doses, long-term. Some cassia cinnamon products contain high levels of coumarin. Coumarin can cause hepatotoxicity in animal models (15299,21920). In humans, very high doses of coumarin from 50-7000 mg daily can result in hepatotoxicity that resolves when coumarin use is discontinued (15302). In most cases, ingestion of cassia cinnamon will not provide a high enough amount of coumarin to cause significant toxicity; however, in especially sensitive people, such as those with liver disease, prolonged ingestion of large amounts of cassia cinnamon might exacerbate the condition.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
Cassia cinnamon 1 gram daily has been used safely in adolescents 13-18 years of age for up to 3 months (89648).
PREGNANCY AND LACTATION: LIKELY SAFE
when consumed in amounts commonly found in foods (4912).
There is insufficient reliable information available about the safety of cassia cinnamon when used in medicinal amounts during pregnancy and breast-feeding. Stay on the safe side and stick to food amounts.
LIKELY SAFE ...when used orally and appropriately, short-term. Eleuthero root extract 300-2000 mg has been used safely in clinical trials lasting up to 3 months (730,1427,2574,7522,11099,15586,91509). There is insufficient reliable information available about the safety of eleuthero when used long-term.
CHILDREN: POSSIBLY SAFE
when used orally in adolescents aged 12-17 years, short-term.
Eleuthero 750 mg three times daily was used for 6 weeks with apparent safety in one clinical trial (75028). There is insufficient reliable information available about the safety of eleuthero in children or adolescents when used long-term.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts. Eurycoma longifolia has been safely used in doses of 400 mg daily for up to 3 months and in doses of 200 mg daily for up to 9 months (17924,18138,93490,97312).
POSSIBLY UNSAFE ...when used orally in excessive amounts, long-term. There are some concerns about the safety of Eurycoma longifolia due to contamination with mercury and lead or adulteration with sildenafil (17925,17926,17927,18137,49087,93494). Some research shows that 36% and 17% of Eurycoma longifolia preparations from Malaysia contain high levels of mercury and lead, respectively (17925,17926,17927,49087). While safety issues related to these contaminants have not been reported in humans, taking high doses of Eurycoma longifolia long-term might cause symptoms of heavy metal poisoning or sildenafil-related adverse effects.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
Animal research suggests that there are no negative effects of Eurycoma longifolia on the offspring (93493). However, research in humans is lacking.
POSSIBLY SAFE ...when used orally and appropriately. A specific fermented wheat germ extract (Avemar) has been used safely in clinical research at doses of 8.5-9 grams once or twice daily for up to 12 months (27703,27704,27706,27708,109632). There is insufficient reliable information available regarding the safety of fermented wheat germ extract when applied topically.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately.
A specific fermented wheat germ extract (Avemar) has been used safely in clinical research at a dose of 6 grams/m2 twice daily for approximately 29 months (27702).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally and appropriately. Ginger has been safely used in multiple clinical trials (721,722,723,5343,7048,7084,7085,7400,7623,11346)(12472,13080,13237,13244,17369,17928,17929,89889,89890,89894)(89895,89898,89899,90102,96252,96253,96259,96260,96669) (101760,101761,101762,103359,107903).
POSSIBLY SAFE ...when used topically and appropriately, short-term (89893,89897).
CHILDREN: LIKELY SAFE
when consumed in the amounts typically found in foods.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
Ginger powder has been used with apparent safety at a dose of up to 750 mg daily for 4 days in girls aged 14-18 years (96255).
PREGNANCY: LIKELY SAFE
when consumed in the amounts typically found in foods.
Ginger is considered a first-line nonpharmacological treatment option for nausea in pregnancy by the American College of Obstetrics and Gynecology (ACOG) (111601). However, it should not be used long-term or without medical supervision and close monitoring.
PREGNANCY: POSSIBLY SAFE
when used for medicinal purposes.
Despite some early reports of adverse effects (721,7083) and one observational study suggesting that taking dried ginger and other herbal supplements during the first 20 weeks of pregnancy marginally increased the chance of stillbirth (96254), most research shows that ginger is unlikely to cause harm to the baby. The risk for major malformations in infants of parents who took ginger when pregnant does not appear to be higher than the baseline rate of 1% to 3% (721,1922,5343,11346,13071,13080,96254). Also, other research suggests that ginger intake during various trimesters does not significantly affect the risk of spontaneous abortion, congenital malformations, stillbirth, perinatal death, preterm birth, low birth weight, or low Apgar scores (18211,90103). Ginger use has been associated with an increase in non-severe vaginal bleeding, including spotting, after week 17 of pregnancy (18211).
LACTATION: LIKELY SAFE
when consumed in the amounts typically found in foods.
There is insufficient reliable information available about the safety of ginger when used for medicinal purposes; avoid amounts greater than those found in foods.
POSSIBLY SAFE ...when horny goat weed extract is used orally and appropriately, short-term. A specific extract of horny goat weed containing 60 mg icariin, 15 mg daidzein, and 3 mg genistein (Xianling Gubao; Tong Ji Tang Pharmacal Company) has been used daily with apparent safety for up to 24 months (14900,97268). Another aqueous extract of horny goat weed containing up to 25.36% icariin has been used in a dose of 300 mL daily with apparent safety for up to 6 months (55452). Another horny goat weed extract has been used with apparent safety at doses up to 1000 mg daily (providing 200 mg icariin) for up to 30 days (108311).
POSSIBLY UNSAFE ...when used orally long-term or in high doses. Long-term use, or taking high doses of some species of horny goat weed, has been linked to serious adverse effects including respiratory arrest (10346).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Horny goat weed might have androgenic activity (10346). Theoretically, it might harm a developing fetus; avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY SAFE ...when used orally, short-term. Kava extracts have been used safely in clinical trials under medical supervision for up to 6 months (2093,2094,2095,4032,7325,15046,15130,18314,18316,18318)(18320,29663,29671,98980,102086,112642). Historically, there has been some concern that kava preparations could induce hepatotoxicity and liver failure in patients taking relatively normal doses, short-term. At least 100 cases of liver toxicity following kava use have been reported. Although liver toxicity is more frequently associated with prolonged use of very high doses (6401,57346), in some cases the use of kava for as little as 1-3 months has been associated with the need for liver transplants, and even death (390,7024,7068,7086,7096,17086,57252)(57254,57297). However, some experts question the clinical validity of several of these cases (11369,11371).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
There is some concern that pyrone constituents in kava can cause loss of uterine tone (19); avoid using.
LACTATION: POSSIBLY UNSAFE
when used orally.
There is concern that the toxic pyrone constituents of kava can pass into breast milk (19); avoid using.
POSSIBLY SAFE ...when used orally and appropriately. L-arginine has been used safely in clinical studies at doses of up to 24 grams daily for up to 18 months (3331,3460,3595,3596,5531,5532,5533,6028,7815,7816)(8014,8473,13709,31943,91195,91196,91963,99264,99267,110380)(110387). A tolerable upper intake level (UL) for arginine has not been established, but the observed safe level (OSL) of arginine intake established in clinical research is 20 grams (31996). ...when used intravenously and appropriately. Parenteral L-arginine is an FDA-approved prescription product (15). ...when used topically and appropriately. L-arginine appears to be safe when 5 grams is applied as a topical cream twice daily for 2 weeks or when a dentifrice is used at a dose of 1.5% w/w for up to 2 years (14913,96806). ...when inhaled, short-term. L-arginine appears to be safe when inhaled twice daily at a dose of 500 mg for up to 2 weeks (96807).
CHILDREN: POSSIBLY SAFE
when used orally in premature infants and children (8474,32286,96803,97392,110391).
...when used intravenously and appropriately (97392). Parenteral L-arginine is an FDA-approved prescription product (15). ...when used topically, short-term. A dentifrice containing L-arginine appears to be safe when used at a dose of 1.5% w/w for up to 2 years in children at least 3.7 years of age (96806). ...when inhaled, short-term. L-arginine appears to be safe when inhaled twice daily at a dose of 500 mg for up to 2 weeks in children at least 13 years of age (96807).
CHILDREN: POSSIBLY UNSAFE
when used intravenously in high doses.
Parenteral L-arginine is an FDA-approved prescription product (15). However, when higher than recommended doses are used, injection site reactions, hypersensitivity reactions, hematuria, and death have occurred in children (16817).
PREGNANCY: POSSIBLY SAFE
when used orally and appropriately, short-term.
L-arginine 12 grams daily for 2 days has been used with apparent safety in pregnancy during the third trimester (11828). L-arginine 3 grams daily has been taken safely during the second and/or third trimesters (31938,110379,110382). ...when used intravenously and appropriately, short-term. Intravenous L-arginine 20-30 grams daily has been used safely in pregnancy for up to 5 days (31847,31933,31961,31978).
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally and appropriately, short-term. Panax ginseng seems to be safe when used for up to 6 months (8813,8814,17736,89741,89743,89745,89746,89747,89748,103044,103477).
POSSIBLY UNSAFE ...when used orally, long-term. There is some concern about the long-term safety due to potential hormone-like effects, which might cause adverse effects with prolonged use (12537). Tell patients to limit continuous use to less than 6 months. There is insufficient reliable information available about the safety of Panax ginseng when used topically.
CHILDREN: LIKELY UNSAFE
when used orally in infants.
Use of Panax ginseng in newborns is associated with intoxication that can lead to death (12). There is limited reliable information available about use in older children (24109,103049); avoid using.
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Ginsenoside Rb1, an active constituent of Panax ginseng, has teratogenic effects in animal models (10447,24106,24107); avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY UNSAFE ...when the spine-covered fruit is used orally. There have been reports of bilateral pneumothorax and bronchial polyp after oral consumption of the spine-covered fruit (818).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Animal research suggests that tribulus might adversely affect fetal development (12674); avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when the fruit extract is used orally and appropriately, short-term. Vitex agnus-castus fruit extract has been used safely in studies at doses up to 40 mg daily, for up to 3 months (7055,7076,7077,7078,7079,12207,13393,15065,90617,90618,96435). There is insufficient reliable information available about the safety of vitex agnus-castus seeds when used orally or topically.
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally.
Theoretically, the hormonal effects of vitex agnus-castus might adversely affect pregnancy or lactation (10979,11456,13393,109439). Animal research shows that taking vitex agnus-castus fruit extract when planning to become pregnant or during pregnancy may increase the risk of infertility, low fetal body weight, abortion, and stillbirth (109439); avoid using.
Below is general information about the interactions of the known ingredients contained in the product HighTest for Men HardKnight Testoster-1 Virility Intensifying Gel. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Theoretically, taking ashwagandha with antidiabetes drugs might increase the risk of hypoglycemia.
 Details
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Theoretically, taking ashwagandha with antihypertensive drugs might increase the risk of hypotension.
Details
Animal research suggests that ashwagandha might lower systolic and diastolic blood pressure (19279). Theoretically, ashwagandha might have additive effects when used with antihypertensive drugs and increase the risk of hypotension.
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Theoretically, taking ashwagandha might increase the sedative effects of benzodiazepines.
Details
There is preliminary evidence that ashwagandha might have an additive effect with diazepam (Valium) and clonazepam (Klonopin) (3710). This may also occur with other benzodiazepines.
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Theoretically, taking ashwagandha might increase the sedative effects of CNS depressants.
Details
Ashwagandha seems to have sedative effects. Theoretically, this may potentiate the effects of barbiturates, other sedatives, and anxiolytics (3710).
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Theoretically, taking ashwagandha might decrease the effects of immunosuppressants.
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Ashwagandha might increase the effects and adverse effects of thyroid hormone.
Details
Concomitant use of ashwagandha with thyroid hormones may cause additive therapeutic and adverse effects. Preliminary clinical research and animal studies suggest that ashwagandha boosts thyroid hormone synthesis and secretion (19281,19282,97292). In one clinical study, ashwagandha increased triiodothyronine (T3) and thyroxine (T4) levels by 41.5% and 19.6%, respectively, and reduced serum TSH levels by 17.4% from baseline in adults with subclinical hypothyroidism (97292).
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Theoretically, using topical capsaicin may increase the risk of ACE inhibitor-induced cough.
Details
There is one case report of a topically applied capsaicin cream contributing to the cough reflex in a patient using an ACEI (12414). However, it is unclear if this interaction is clinically significant.
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Theoretically, capsicum may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Details
In vitro research shows that capsicum might increase the effects of antiplatelet drugs (12406,12407). Also, population research shows that capsicum is associated with an increased risk of self-reported bleeding in patients taking warfarin (12405,20348). However, clinical research shows that taking a single dose of capsaicin (Asian Herbex Ltd.), the active ingredient in capsicum, 400-800 mcg orally in combination with aspirin 500 mg does not decrease platelet aggregation when compared with taking aspirin 500 mg alone. Also, there was no notable effect on measures of platelet aggregation with capsaicin (92990). It is unclear whether capsaicin must be used in more than a single dose to affect platelet aggregation.
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Theoretically, taking capsicum with antidiabetes drugs might increase the risk of hypoglycemia.
Details
Preliminary clinical research shows that consuming capsicum 5 grams along with a glucose drink attenuates the rise in plasma glucose after 30 minutes by 21%, decreases the 2-hour postprandial area under the curve of plasma glucose by 11%, and increases the 2-hour postprandial area under the curve of plasma insulin by 58% in healthy individuals when compared with placebo (40453,40614). Other clinical research shows that taking capsicum 5 mg daily for 28 days significantly reduces postprandial blood glucose and insulin levels, but not fasting blood glucose and insulin levels, in patients with gestational diabetes (96457).
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Theoretically, taking capsicum with aspirin might reduce the bioavailability of aspirin.
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Animal research shows that acute or chronic intake of capsicum pepper reduces oral aspirin bioavailability (22617). This has not been shown in humans.
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Theoretically, taking capsicum with ciprofloxacin might increase levels and adverse effects of ciprofloxacin.
Details
Animal research shows that concomitant use of capsaicin, the active constituent of capsicum, and ciprofloxacin increases the bioavailability of ciprofloxacin by up to 70% (22613).
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Theoretically, taking capsicum with theophylline might increase the levels and adverse effects of theophylline.
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Theoretically, cassia cinnamon may have additive effects with antidiabetes drugs.
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Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.
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There is some concern that ingesting large amounts of cassia cinnamon for an extended duration might cause hepatotoxicity in some people. Cassia cinnamon contains coumarin, which can cause hepatotoxicity in animal models (15299,21920). In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin use is discontinued (15302,97249). Lower amounts might also cause liver problems in sensitive people, such as those with liver disease or those taking potentially hepatotoxic agents.
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Theoretically, eleuthero may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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Theoretically, eleuthero might have additive effects when used with antidiabetes drugs.
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Animal research suggests that certain constituents of eleuthero have hypoglycemic activity in both healthy and diabetic animals (7591,73535,74932,74956,74988,74990). A small study in adults with type 2 diabetes also shows that taking eleuthero for 3 months can lower blood glucose levels (91509). However, one very small study in healthy individuals shows that taking powdered eleuthero 3 grams, 40 minutes prior to a 75-gram oral glucose tolerance test, significantly increases postprandial blood glucose levels when compared with placebo (12536). These contradictory findings might be due to patient-specific variability and variability in active ingredient ratios.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP1A2.
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In vitro and animal research suggest that standardized extracts of eleuthero inhibit CYP1A2 (7532). This effect has not been reported in humans.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP2C9.
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In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2C9 (7532). This effect has not been reported in humans.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP2D6.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP3A4.
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Eleuthero might increase serum digoxin levels and increase the risk of side effects.
Details
In one case report, a 74-year-old male who was stabilized on digoxin presented with an elevated serum digoxin level after starting an eleuthero supplement, without symptoms of toxicity. After stopping the supplement, serum digoxin levels returned to normal (543). It is not clear whether this was due to a pharmacokinetic interaction or to interference with the digoxin assay (15585). Although the product was found to be free of digoxin and digitoxin (543), it was not tested for other contaminants (797).
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Theoretically, eleuthero might interfere with immunosuppressive drugs because of its immunostimulant activity.
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Theoretically, eleuthero might decrease levels of drugs metabolized by OATP.
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In vitro research suggests that eleuthero inhibits OATP2B1, which might reduce the bioavailability of oral drugs that are substrates of OATP2B1 (35450). Due to the weak inhibitory effect identified in this study, this interaction is not likely to be clinically significant.
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Theoretically, eleuthero might increase levels of P-glycoprotein substrates.
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Theoretically, Eurycoma longifolia might increase levels CYP1A2 substrates.
Details
In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP1A2 enzymes (93489). This effect has not been reported in humans.
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Theoretically, Eurycoma longifolia might increase levels of CYP2A6 substrates.
Details
In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP2A6 enzymes (93489). This effect has not been reported in humans.
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Theoretically, Eurycoma longifolia might increase levels of CYP2C19 substrates.
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In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP2C19 enzymes (93489). This effect has not been reported in humans.
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Eurycoma longifolia can reduce the levels and clinical effects of propranolol.
Details
A small clinical study in healthy persons shows that taking a single dose of a water-based Eurycoma longifolia extract 200 mg, in combination with a single dose of propranolol 80 mg, reduces the propranolol area under the curve (AUC) by 29%, reduces the peak concentration by 42%, and increases time to peak concentration by 86% when compared with control. Since the elimination half-life of propranolol did not change, it seems that Eurycoma longifolia alters the kinetics of propranolol by decreasing its absorption in the gut, and not by altering its metabolism (17923). It is not known if separating administration will prevent this interaction.
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Theoretically, Eurycoma longifolia may further increase levels of testosterone.
Details
A clinical study in aging males with testosterone levels below 300 ng/dL shows that taking a specific water extract of Eurycoma longifolia roots (Physta; Biotropics Malaysia) 100-200 mg daily with breakfast for 12 weeks increases total testosterone levels by 8% to 11% when compared with placebo (108451). It is unclear whether this increase would occur in individuals with normal testosterone levels.
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Theoretically, fermented wheat germ extract might decrease the effects of immunosuppressants.
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Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.
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Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation (7622,12634,20321,20322,20323,96257). However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials (96257). Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.
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Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.
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Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.
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Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects (12633). Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone (107901).
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Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.
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In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time (20401).
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Theoretically, ginger might increase the levels of CYP1A2 substrates.
Details
In vitro research shows that ginger inhibits CYP1A2 activity (111544). However, this interaction has not been reported in humans.
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Theoretically, ginger might increase the levels of CYP2B6 substrates.
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In vitro research shows that ginger inhibits CYP2B6 activity (111544). However, this interaction has not been reported in humans.
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Theoretically, ginger might increase the levels of CYP2C9 substrates.
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In vitro research shows that ginger inhibits CYP2C9 activity (111544). However, this interaction has not been reported in humans.
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Ginger might increase or decrease the levels of CYP3A4 substrates.
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In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity (111544,111644). Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644).
Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates (111404). However, this interaction has not been reported in humans. |
Theoretically, ginger might increase levels of losartan and the risk of hypotension.
Details
In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan (102459). It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.
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Theoretically, ginger might increase levels of metronidazole.
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In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced (20350).
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Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.
Details
Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone (20324).
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Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.
Details
In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates (111544,111644). Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644).
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Ginger might increase the risk of bleeding with phenprocoumon.
Details
Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea (12880).
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Ginger might increase the risk of bleeding with warfarin.
Details
Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation (7622,12634,20321,20322,20323). In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin (12880). In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen (20349). A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months (20348). However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin (12881,15176). Until more is known, monitor INRs closely in patients taking large amounts of ginger.
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Theoretically, horny goat weed might increase the risk of bleeding.
Details
In vitro research and animal research shows that horny goat weed can inhibit platelet aggregation and thrombus formation (105832). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the risk of hypotension.
Details
Laboratory research suggests that horny goat weed might have hypotensive effects (10346). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the effects and side effects of CYP1A2 substrates.
Details
In vitro, horny goat weed leaf extract inhibits CYP1A2 (97267). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the effects and side effects of CYP2B6 substrates.
Details
In vitro, horny goat weed leaf extract inhibits CYP2B6 (97267). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the effects and side effects of CYP3A4 substrates.
Details
In vitro, horny goat weed extract inhibits CYP3A4 and suppresses CYP3A4 mRNA expression (112708). This effect has not been reported in humans.
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Theoretically, concomitant use of horny goat weed with estrogens might increase their therapeutic and adverse effects.
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Combining kava with alcohol may increase the risk of sedation and/or hepatotoxicity.
Details
Kava has CNS depressant effects (11373,18316). Concomitant use of kava with other CNS depressants can increase the risk of drowsiness and motor reflex depression (2093,2098). Additionally, kava has been associated with over 100 cases of hepatotoxicity. There is some concern that kava can adversely affect the liver, especially when used in combination with hepatotoxic drugs (7024,7068,7086,7096,17086,57346). Clinical practice guidelines from a joint taskforce of the World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Treatments (CANMAT) recommend that alcohol not be used with kava (110318). |
Combining kava with CNS depressants can have additive sedative effects.
Details
Kava has CNS depressant effects (11373,18316). Concomitant use of kava with other CNS depressants can increase the risk of drowsiness and motor reflex depression (2093,2098). Clinical practice guidelines from a joint taskforce of the World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Treatments (CANMAT) recommend that CNS depressants, including alcohol and benzodiazepines, not be used with kava (110318).
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It is unclear if kava inhibits CYP1A2; research is conflicting.
Details
Although in vitro research and a case report suggest that kava inhibits CYP1A2 (8743,12479,88593), more robust clinical evidence shows that kava has no effect on CYP1A2. In a clinical study in healthy volunteers, taking kava 1000 mg twice daily (containing a daily dose of 138 mg kavalactones) for 28 days had no effect on CYP1A2 activity (13536,98979).
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Theoretically, kava might increase levels of CYP2C19 substrates.
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Theoretically, kava might increase levels of CYP2C9 substrates.
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It is unclear if kava inhibits CYP1A2; research is conflicting.
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Kava might increase levels of CYP2E1 substrates.
Details
In a clinical study in healthy volunteers, taking kava 1000 mg twice daily (containing a daily dose of 138 mg kavalactones) for 28 days inhibited the metabolism of CYP2E1 substrates (13536).
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It is unclear if kava inhibits CYP3AA; research is conflicting.
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Although in vitro research suggests that kava inhibits CYP3A4 (8743,12479), more robust clinical evidence shows that kava has no effect on CYP3A4. In a clinical study in healthy volunteers, taking kava 1000 mg twice daily (containing a daily dose of 138 mg kavalactones) for 28 days had no effect on CYP3A4 activity (13536,98979).
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Combining kava and haloperidol might increase the risk of cardiovascular adverse effects and hypoxia.
Details
Atrial flutter and hypoxia has been reported for a patient who received intramuscular injections of haloperidol and lorazepam after using kava orally. The side effects were attributed to kava-induced inhibition of CYP2D6, but might also have been related to additive adverse effects with the concomitant use of haloperidol, lorazepam, and kava (88593).
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Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
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It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Details
In vitro research shows that kava can inhibit P-gp efflux (15131). However, a clinical study in healthy volunteers shows that taking kava standardized to provide 225 mg kavalactones daily for 14 days does not affect the pharmacokinetics of digoxin, a P-gp substrate (15132,98979). It is possible that the use of other P-gp substrates or higher doses of kava might still inhibit P-gp.
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Taking kava with ropinirole might increase the risk for dopaminergic toxicity.
Details
A case of visual hallucinations and paranoid delusions has been reported for a patient who used kava in combination with ropinirole. The adverse effects were attributed to kava-induced inhibition of CYP1A2, which may have reduced the metabolism of ropinirole, resulting in excessive dopaminergic stimulation (88593).
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Theoretically, concomitant use of L-arginine and ACE inhibitors may increase the risk for hypotension and hyperkalemia.
Details
Combining L-arginine with some antihypertensive drugs, especially ACE inhibitors, seems to have additive vasodilating and blood pressure-lowering effects (7822,20192,31854,31916). Furthermore, ACE inhibitors can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients (32213,32218). Theoretically, concomitant use of ACE inhibitors with L-arginine may increases the risk of hyperkalemia.
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Theoretically, concomitant use of L-arginine and ARBs may increase the risk of hypotension and hyperkalemia.
Details
L-arginine increases nitric oxide, which causes vasodilation (7822). Combining L-arginine with ARBs seems to increase L-arginine-induced vasodilation (31854). Furthermore, ARBs can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients (32213,32218). Theoretically, concomitant use of ARBs with L-arginine may increases the risk of hyperkalemia.
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Theoretically, concomitant use of L-arginine with anticoagulant and antiplatelet drugs might have additive effects and increase the risk of bleeding.
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Theoretically, concomitant use of L-arginine might have additive effects with antidiabetes drugs.
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Theoretically, concomitant use of L-arginine and antihypertensive drugs may increase the risk of hypotension.
Details
L-arginine increases nitric oxide, which causes vasodilation (7822). Clinical evidence shows that L-arginine can reduce blood pressure in some individuals with hypertension (7818,10636,31871,32201,32167,32225,31923,32232,110383,110384). Furthermore, combining L-arginine with some antihypertensive drugs seems to have additive vasodilating and blood pressure-lowering effects (7822,20192,31854,31916).
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Theoretically, concurrent use of isoproterenol and L-arginine might result in additive effects and hypotension.
Details
Preliminary clinical evidence suggests that L-arginine enhances isoproterenol-induced vasodilation in patients with essential hypertension or a family history of essential hypertension (31932).
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Theoretically concomitant use of potassium-sparing diuretics with L-arginine may increases the risk of hyperkalemia.
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Theoretically, concurrent use of sildenafil and L-arginine might increase the risk for hypotension.
Details
In vivo, concurrent use of L-arginine and sildenafil has resulted in increased vasodilation (7822,8015,10636). Theoretically, concurrent use might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported (105065).
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Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
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Although Panax ginseng has shown antiplatelet effects in the laboratory, it is unlikely to increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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In vitro evidence suggests that ginsenoside constituents in Panax ginseng might decrease platelet aggregation (1522,11891). However, research in humans suggests that ginseng does not affect platelet aggregation (11890). Animal research indicates low oral bioavailability of Rb1 and rapid elimination of Rg1, which might explain the discrepancy between in vitro and human research (11153). Until more is known, use with caution in patients concurrently taking anticoagulant or antiplatelet drugs.
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Theoretically, taking Panax ginseng with antidiabetes drugs might increase the risk of hypoglycemia.
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Clinical research suggests that Panax ginseng might decrease blood glucose levels (89740). Monitor blood glucose levels closely.
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Theoretically, taking Panax ginseng with caffeine might increase the risk of adverse stimulant effects.
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Theoretically, Panax ginseng might decrease levels of drugs metabolized by CYP1A1.
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In vitro research shows that Panax ginseng can induce the CYP1A1 enzyme (24104).
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Theoretically, Panax ginseng might increase levels of drugs metabolized by CYP2D6. However, research is conflicting.
Details
There is some evidence that Panax ginseng can inhibit the CYP2D6 enzyme by approximately 6% (1303,51331). In addition, in animal research, Panax ginseng inhibits the metabolism of dextromethorphan, a drug metabolized by CYP2D6, by a small amount (103478). However, contradictory research suggests Panax ginseng might not inhibit CYP2D6 (10847). Until more is known, use Panax ginseng cautiously in patients taking drugs metabolized by these enzymes.
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Theoretically, Panax ginseng might increase or decrease levels of drugs metabolized by CYP3A4.
Details
Panax ginseng may affect the clearance of drugs metabolized by CYP3A4. One such drug is imatinib. Inhibition of CYP3A4 was believed to be responsible for a case of imatinib-induced hepatotoxicity (89764). In contrast, Panax ginseng has been shown to increase the clearance of midazolam, another drug metabolized by CYP3A4 (89734,103478). Clinical research shows that Panax ginseng can reduce midazolam area under the curve by 44%, maximum plasma concentration by 26%, and time to reach maximum plasma concentration by 29% (89734). Midazolam metabolism was also increased in animals given Panax ginseng (103478). Until more is known, use Panax ginseng cautiously in combination with CYP3A4 substrates.
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Theoretically, concomitant use of large amounts of Panax ginseng might interfere with hormone replacement therapy.
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Theoretically, Panax ginseng might decrease blood levels of oral or intravenous fexofenadine.
Details
Animal research suggests that taking Panax ginseng in combination with oral or intravenous fexofenadine may reduce the bioavailability of fexofenadine. Some scientists have attributed this effect to the ability of Panax ginseng to increase the expression of P-glycoprotein (24101).
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Theoretically, Panax ginseng might reduce the effects of furosemide.
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There is some concern that Panax ginseng might contribute to furosemide resistance. There is one case of resistance to furosemide diuresis in a patient taking a germanium-containing ginseng product (770).
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Theoretically, Panax ginseng might increase the effects and adverse effects of imatinib.
Details
A case of imatinib-induced hepatotoxicity has been reported for a 26-year-old male with chronic myelogenous leukemia stabilized on imatinib for 7 years. The patient took imatinib 400 mg along with a Panax ginseng-containing energy drink daily for 3 months. Since imatinib-associated hepatotoxicity typically occurs within 2 years of initiating therapy, it is believed that Panax ginseng affected imatinib toxicity though inhibition of cytochrome P450 3A4. CYP3A4 is the primary enzyme involved in imatinib metabolism (89764).
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Theoretically, Panax ginseng use might interfere with immunosuppressive therapy.
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Panax ginseng might have immune system stimulating properties (3122).
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Theoretically, taking Panax ginseng with insulin might increase the risk of hypoglycemia.
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Clinical research suggests that Panax ginseng might decrease blood glucose levels (89740). Insulin dose adjustments might be necessary in patients taking Panax ginseng; use with caution.
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Although Panax ginseng has demonstrated variable effects on cytochrome P450 3A4 (CYP3A4), which metabolizes lopinavir, Panax ginseng is unlikely to alter levels of lopinavir/ritonavir.
Details
Lopinavir is metabolized by CYP3A4 and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Panax ginseng has shown variable effects on CYP3A4 activity in humans (89734,89764). However, taking Panax ginseng (Vitamer Laboratories) 500 mg twice daily for 14 days did not alter the pharmacokinetics of lopinavir/ritonavir in 12 healthy volunteers (93578).
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Theoretically, Panax ginseng may increase the clearance of midazolam.
Details
Midazolam is metabolized by cytochrome P450 3A4 (CYP3A4). Clinical research suggests that Panax ginseng can reduce midazolam area under the curve by 44%, maximum plasma concentration by 26%, and time to reach maximum plasma concentration by 29% (89734). Midazolam metabolism was also increased in animals given Panax ginseng (103478).
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Theoretically, Panax ginseng can interfere with MAOI therapy.
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Theoretically, taking Panax ginseng with nifedipine might increase serum levels of nifedipine and the risk of hypotension.
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Preliminary clinical research shows that concomitant use can increase serum levels of nifedipine in healthy volunteers (22423). This might cause the blood pressure lowering effects of nifedipine to be increased when taken concomitantly with Panax ginseng.
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Theoretically, Panax ginseng has an additive effect with drugs that prolong the QT interval and potentially increase the risk of ventricular arrhythmias. However, research is conflicting.
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Theoretically, taking Panax ginseng with raltegravir might increase the risk of liver toxicity.
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A case report suggests that concomitant use of Panax ginseng with raltegravir can increase serum levels of raltegravir, resulting in elevated liver enzymes levels (23621).
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Theoretically, Panax ginseng might increase or decrease levels of selegiline, possibly altering the effects and side effects of selegiline.
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Animal research shows that taking selegiline with a low dose of Panax ginseng extract (1 gram/kg) reduces selegiline bioavailability, while taking a high dose of Panax ginseng extract (3 grams/kg) increases selegiline bioavailability (103053). More research is needed to confirm these effects.
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Theoretically, taking Panax ginseng with stimulant drugs might increase the risk of adverse stimulant effects.
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Panax ginseng might affect the clearance of warfarin. However, this interaction appears to be unlikely.
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There has been a single case report of decreased effectiveness of warfarin in a patient who also took Panax ginseng (619). However, it is questionable whether Panax ginseng was the cause of this decrease in warfarin effectiveness. Some research in humans and animals suggests that Panax ginseng does not affect the pharmacokinetics of warfarin (2531,11890,17204,24105). However, other research in humans suggests that Panax ginseng might modestly increase the clearance of the S-warfarin isomer (15176). More evidence is needed to determine whether Panax ginseng causes a significant interaction with warfarin.
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Taking tribulus with antidiabetes drugs might increase the risk of hypoglycemia.
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Clinical research shows that Tribulus can lower blood glucose levels in adults with type 2 diabetes who are taking antidiabetes medications (97327).
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Theoretically, taking tribulus with antihypertensive drugs might increase the risk of hypotension.
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Theoretically, tribulus might increase the levels and clinical effects of lithium.
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Tribulus is thought to have diuretic properties (12681). Due to these potential diuretic effects, tribulus might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.
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Theoretically, vitex agnus-castus could interfere with the activity of antipsychotic drugs.
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Theoretically, vitex agnus-castus could interfere with oral contraceptives.
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Theoretically, vitex agnus-castus could interfere with dopamine agonists.
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Vitex agnus-castus might potentiate the actions of dopaminergic agonists due to possible dopaminergic effects (10122).
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Theoretically, vitex agnus-castus could interfere with the activity of estrogens.
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Theoretically, dopaminergic effects of vitex agnus-castus could interfere with metoclopramide.
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Below is general information about the adverse effects of the known ingredients contained in the product HighTest for Men HardKnight Testoster-1 Virility Intensifying Gel. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
General
...Orally, ashwagandha seems to be well-tolerated.
Topically, no adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.
Most Common Adverse Effects:
Orally: Diarrhea, gastrointestinal upset, nausea, and vomiting. However, these adverse effects do not commonly occur with typical doses.
Serious Adverse Effects (Rare):
Orally: Some case reports raise concerns about acute liver failure, hepatic encephalopathy, and the need for liver transplantation with ashwagandha treatment.
Dermatologic ...Orally, dermatitis has been reported in three of 42 patients in a clinical trial (19276).
Endocrine ...A case report describes a 73-year-old female who had taken an ashwagandha root extract (unspecified dose) for 2 years to treat hypothyroidism which had been previously managed with levothyroxine. The patient was diagnosed with hyperthyroidism after presenting with supraventricular tachycardia, chest pain, tremor, dizziness, fatigue, irritability, hair thinning, and low thyroid stimulating hormone (TSH) levels. Hyperthyroidism resolved after discontinuing ashwagandha (108745).
Gastrointestinal ...Orally, large doses may cause gastrointestinal upset, diarrhea, and vomiting secondary to irritation of the mucous and serous membranes (3710). When taken orally, nausea and abdominal pain (19276,110490) and gastritis and flatulence (90651) have been reported.
Genitourinary ...In one case report, a 28-year-old male with a decrease in libido who was taking ashwagandha 5 grams daily over 10 days subsequently experienced burning, itching, and skin and mucous membrane discoloration of the penis, as well as an oval, dusky, eroded plaque (3 cm) with erythema on the glans penis and prepuce (32537).
Hepatic ...Orally, ashwagandha in doses of 154-1350 mg daily has played a role in several case reports of liver injury. In most of these cases, other causes of liver injury were excluded, and liver failure did not occur. Symptoms included jaundice, pruritus, malaise, fatigue, lethargy, weight loss, nausea, diarrhea, abdominal pain, stool discoloration, and dark urine. Symptom onset was typically 5-180 days from first intake, although in some cases onset occurred after more than 12 months of use (102686,107372,110490,110491,111533,111535,112111). Laboratory findings include elevated aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase, and serum bilirubin (112111). In most cases, liver enzymes normalized within 1-5 months after discontinuation of ashwagandha (102686,107372,110491,111535,112111). However, treatment with corticosteroids, lactulose, ornithine, ursodeoxycholic acid, and plasmapheresis, among other interventions, was required in one case (111533). Rarely, use of oral ashwagandha has been reported to cause hepatic encephalopathy and liver failure requiring liver transplantation (110490).
Neurologic/CNS ...Orally, ashwagandha has been reported to cause drowsiness (110492). Headache, neck pain, and blurry vision have been reported in a 47-year-old female taking ashwagandha, cannabis, and venlafaxine. Imaging over the course of multiple years and hospital admissions indicated numerous instances of intracranial hemorrhage and multifocal stenosis of intracranial arteries, likely secondary to reversible cerebral vasoconstriction syndrome (RCVS) (112113). It is unclear whether the RCVS and subsequent intracranial hemorrhages were precipitated by ashwagandha, cannabis, or venlafaxine.
General
...Orally, capsicum is generally well tolerated in amounts typically found in food or when the extract is used in doses of up to 200 mg daily.
Topically and intranasally, capsaicin, a constituent of capsicum, is generally well tolerated.
Most Common Adverse Effects:
Orally: Belching, bloating, burning, diarrhea, dyspepsia, gas, headache, mild constipation, nausea, rhinorrhea, skin flushing, and sweating.
Serious Adverse Effects (Rare):
Orally: Cases of myocardial infarction and hypertensive crisis have been reported.
Cardiovascular
...Orally, palpitation was reported in one clinical trial (105196).
One case of myocardial infarction has been reported in a 41-year-old male without cardiovascular risk factors; the event was attributed to the use of an oral capsicum pepper pill that the patient had been taking for weight loss (40768). Another case of coronary vasospasm and acute myocardial infarction has been reported for a healthy 29-year-old male; the event was attributed to the use of a topical capsicum-containing patch that the patient had been applying to the middle of the back for 6 days (40658). Two cases of arterial hypertensive crisis have been reported for individuals who ingested a large amount of peppers and chili peppers the day before. One of the patients also had an acute myocardial infarction, and the other had high levels of thyroid stimulating hormone (40569,40606).
Dermatologic
...Orally, capsicum or its constituent capsaicin may cause urticaria and skin wheals in rare cases (96457,105203).
Topically, capsicum can cause a prickling sensation, itching, pain, burning, edema, stinging, irritation, rash, and erythema. About 1 in 10 patients who use capsaicin topically discontinue treatment because of adverse effects. These effects seem to occur more often with topical formulations containing higher concentrations of capsaicin, the active constituent of capsicum. Side effects tend to diminish with continued use (12401,15260,15261,40358,40439,40483,40547,40676,40682,40719)(40784,40847,92979,92983,92984,96453,105193,105197,105202,111514). In one case, application of a capsaicin 8% patch (Qutenza) for 60 minutes caused a second-degree burn, characterized by burning, erythema, severe pain, and blistering at the administration site. The burn was treated with topical corticosteroids, but 9 months later neuropathic pain persisted, resulting in limited mobility. It is unclear whether the mobility sequalae were caused by topical capsaicin or the patient's pre-existing neurological disorders (111514). Skin contact with fresh capsicum fruit can also cause irritation or contact dermatitis (12408).
Intranasally, capsaicin can cause nasal burning and pain in most patients. It also often causes lacrimation, sneezing, and excessive nasal secretion; however, these side effects appear to diminish with repeat applications (14323,14329,14358). In some cases, the burning sensation disappears after 5-8 applications (14351,14358). In some cases, patients are pretreated with intranasal lidocaine to decrease the pain of intranasal capsaicin treatment. However, even with lidocaine pretreatment, patients seem to experience significant pain (14324).
Gastrointestinal
...Orally, capsicum can cause upper abdominal discomfort, including irritation, fullness, dyspepsia, gas, bloating, nausea, epigastric pain and burning, anal burning, diarrhea, mild constipation, and belching (12403,12410,40338,40427,40456,40503,40560,40584,40605,40665)(40718,40725,40745,40808,40828,96456,96457,105194,105196).
There is a case report of a 3-year-old female who experienced a burning and swollen mouth and lips after touching the arm of a parent that had been treated with a capsaicin patch and then placing the fingers in the mouth (105199). Excessive amounts of capsaicin can lead to gastroenteritis and hepatic necrosis (12404). In a case report, a 40-year-old male with diabetes consumed white wine daily and chewed cayenne which was thought to result in black teeth stains and loss of enamel (40809). Some preliminary research links ingestion of capsaicin with stomach and gallbladder cancer; however the link may be due to contamination of capsaicin products with carcinogens (40771).
Topically, capsaicin can cause diarrhea and vomiting (105202).
Immunologic ...In a case report, a 34-year-old female had anaphylaxis involving difficulty breathing and stupor and also urticaria after consuming a red bell pepper, which is in the capsicum genus. The causal chemical was theorized to be 1,3-beta-glucanase (92978). In another case report, a 33-year-old female experienced angioedema, difficulty breathing and swallowing, and urticaria after ingesting raw green and red peppers (92982).
Neurologic/CNS ...Orally, capsicum can cause sweating and flushing of the head and neck, lacrimation, headache, faintness, and rhinorrhea (7005,12410,105196,105203). Topically, applying capsaicin can cause headache (96450,105202). Injection of capsaicin into the intermetatarsal space has also been associated with headache (96454).
Ocular/Otic
...Topically, capsicum can be extremely irritating to the eyes and mucous membranes.
Capsicum oleoresin, an oily extract in pepper self-defense sprays, causes intense eye pain. It can also cause erythema, blepharospasm, tearing, shortness of breath, and blurred vision. In rare cases, corneal abrasions have occurred (12408,12409,40345,40348,40383,40720,40857).
Inhalation of capsicum can cause eye irritation, and allergic alveolitis (5885). In a case report, a 38-year-old female had acute anterior uveitis that developed about 12 hours after using a specific patch (Isola Capsicum N Plus) that contained capsaicin 1.5 mg per patch and methyl salicylate 132 mg per patch for neck pain. The uveitis was controlled with topical steroids and did not recur (92977).
Oncologic ...Population research suggests that moderate to high intake of capsaicin, the active constituent of capsicum, is associated with an increased risk of gastric cancer, while low intake is associated with a decreased risk. It is not clear from the study what amount of capsaicin is considered high versus low intake (92988). Additionally, some research suggests that any link may be due to contamination of capsaicin products with carcinogens (40771).
Pulmonary/Respiratory
...Orally, difficulty breathing was reported in a clinical trial (105196).
Topically, nasopharyngitis related to the use of a cream containing capsaicin has been reported (105202).
Inhalation of capsicum and exposure to capsicum oleoresin spray can cause cough, dyspnea, pain in the nasal passages, sneezing, rhinitis, and nasal congestion (5885,15016,40522,40546,40647). In rare cases, inhalation of the capsicum oleoresin or pepper spray has caused cyanosis, apnea, respiratory arrest and death in people. Death was caused by asphyxiation probably due to acute laryngeal edema and bronchoconstriction from inhalation of the capsicum oleoresin spray (40546,40672,40837,40879).
In a case report, a 47-year-old female who was exposed to capsaicin gas for more than 20 minutes experienced acute cough, shortness of breath, short-term chest pain, wheezing, and difficulty breathing for months afterwards (92980). In rare cases, exposure to capsicum oleoresin spray resulted in apnea, pulmonary injury, cyanosis, and even respiratory arrest (40383,40546).
General
...Orally, cassia cinnamon appears to be well-tolerated.
Significant side effects have not been reported in most patients.
Most Common Adverse Effects:
Topically: Burning mouth, stomatitis.
Dermatologic
...In one clinical trial, a rash was reported in one patient taking cassia cinnamon 1 gram daily for 90 days (17011).
In one case, a 58-year-old female with a documented allergy to topically applied cinnamic alcohol presented with eyelid dermatitis, which was found to be a manifestation of systemic contact dermatitis to cinnamon in the diet. Symptoms improved in two days and completely cleared five days after discontinuing the addition of cinnamon to food products (95599). In other case reports, two adults presented with allergic contact cheilitis following the ingestion of chai tea with cinnamon and yogurt with cinnamon. Cinnamon components were confirmed as the causative allergic agents with patch tests, and both cases of allergic contact cheilitis completely resolved upon cessation of the cinnamon-containing products (113516,113515).
Topically, allergic skin reactions and stomatitis from toothpaste flavored with cassia cinnamon have been reported (11915,11920). Intraoral allergic reactions with symptoms of tenderness and burning sensations of the oral mucosa have also been reported in patients using breath fresheners, toothpaste, mouthwash, candy, or chewing gum containing cinnamon, cinnamic aldehyde or cinnamic alcohol as flavoring agents. Glossodynia, or burning mouth syndrome, has also been reported in a 62-year-old female who ate apples dipped in cinnamon nightly (95598), and allergic contact dermatitis has been reported in a teenage female using a homemade cinnamon sugar face scrub (95596).
Endocrine ...In one clinical trial, a hypoglycemic seizure was reported in one patient taking cassia cinnamon 1 gram daily for 3 months. The event occurred one day after enrolling in the study (89648). It is unclear if cassia cinnamon caused this event.
Hepatic ...There is some concern about the safety of ingesting large amounts of cassia cinnamon for extended durations due to its coumarin content. Coumarin can cause hepatotoxicity in animal models (15299). In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin is discontinued (15302). In clinical trials, taking cassia cinnamon 360 mg to 12 grams daily for 3 months did not significantly increase levels of aspartate transaminase (AST) or alanine transaminase (ALT) (21918,96280,108259). However, in one case report, acute hepatitis with elevated AST and ALT occurred in a 73-year-old female who started taking a cinnamon supplement (dose unknown) one week prior to admission. The cinnamon supplement was added on to high-dose rosuvastatin, which may have led to additive adverse hepatic effects. After discontinuing both products, liver function returned to normal, and the patient was able to restart rosuvastati without further complications (97249). In most cases, ingestion of cassia cinnamon won't provide a high enough amount of coumarin to cause significant toxicity; however, in especially sensitive people, such as those with liver disease or taking potentially hepatotoxic agents, prolonged ingestion of large amounts of cassia cinnamon might exacerbate the condition.
Immunologic ...An unspecified allergic reaction was reported in one patient taking cassia cinnamon 1 gram daily for 3 months (89648).
General
...Orally, eleuthero root is generally well tolerated when used short-term.
Most Common Adverse Effects:
Orally: Diarrhea, dyspepsia, gastrointestinal upset, headache, nausea, and urticaria.
Cardiovascular ...Orally, increased blood pressure has been reported in children with hypotension taking eleuthero in one clinical study (74980). Eleuthero has been reported to cause tachycardia, hypertension, and pericardial pain in patients with rheumatic heart disease or atherosclerosis. It is unclear if these effects were caused by eleuthero, or by the cardioglycoside-containing herb, silk vine (Periploca sepium), which is a common adulterant found in eleuthero products (12,797,6500).
Dermatologic ...Orally, eleuthero has been reported to cause rash in some clinical studies (75013,75028).
Gastrointestinal ...Orally, eleuthero has been reported to cause dyspepsia, nausea, diarrhea, and gastrointestinal upset in some patients (74938,75028,91510).
Genitourinary ...Orally, mastalgia and uterine bleeding were reported in 7. 3% of females taking eleuthero 2 grams daily in one clinical study (6500,11099). These adverse effects seem to be more likely with higher doses.
Neurologic/CNS
...Orally, headaches have been reported in 9.
8% of people taking eleuthero in one clinical study (11099).
In one case report, a 53-year-old female developed spontaneous subarachnoid hemorrhage associated with the use of an herbal supplement containing red clover, dong quai, and eleuthero (70419). It is unclear if this event was related to the use of eleuthero, the other ingredients, the combination, or another cause entirely.
Psychiatric ...Orally, nervousness has been reported in 7. 3% of people taking eleuthero in one clinical study (11099). Eleuthero has also been reported to cause slight anxiety, irritability, and melancholy in some patients (6500,11099). These adverse effects seem to be more likely to occur with higher doses.
General
...Orally, Eurycoma longifolia seems to be well tolerated.
Most Common Adverse Effects:
Orally: None reported.
Endocrine ...Some research in both humans and animals suggests that Eurycoma longifolia might increase testosterone levels (17924). If testosterone levels are increased beyond the normal range, there is risk of testosterone-related side effects which could include acne, insulin resistance, hepatotoxicity, and others.
General
...Orally, fermented wheat germ extract seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, nausea.
Gastrointestinal ...Orally, fermented wheat germ extract may cause diarrhea, nausea, flatulence, satiation, soft stools, and constipation. In one clinical study, diarrhea and nausea with or without vomiting were reported in 6% and 3% of patients, respectively (27703).
General
...Orally, ginger is generally well tolerated.
However, higher doses of 5 grams per day increase the risk of side effects and reduce tolerability. Topically, ginger seems to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal discomfort, burping, diarrhea, heartburn, and a pepper-like irritant effect in the mouth and throat. However, some of these mild symptoms may be reduced by ingesting encapsulated ginger in place of powdered ginger.
Topically: Dermatitis in sensitive individuals.
Cardiovascular ...Orally, use of ginger resulted in mild arrhythmia in one patient in a clinical trial (16306).
Dermatologic
...Orally, ginger can cause hives (17933), as well as bruising and flushing (20316) or rash (20316).
Topically, ginger can cause dermatitis in sensitive individuals (12635,46902).
Gastrointestinal
...Orally, common side effects of ginger include nausea (17933,22602,89898,101761), belching (10380,103359), dry mouth (103359), dry retching (10380), vomiting (10380), burning sensation (10380), oral numbness (22602), abdominal discomfort (5343,89898,96253), heartburn (5343,7624,12472,16306,20316,51845,89894,89895,89898,89899)(101760,101761,101762,111543), diarrhea (5343,101760), constipation (89898,101760,101761), or a transient burning or "chilly hot" sensation of the tongue and throat (52076).
Orally, Number Ten, a specific product composed of rhubarb, ginger, astragalus, red sage, and turmeric, can increase the incidence of loose stools (20346).
Four cases of small bowel obstruction due to ginger bolus have been reported following the ingestion of raw ginger without sufficient mastication (chewing). In each case, the bolus was removed by enterotomy. Ginger is composed of cellulose and therefore is resistant to digestion. It can absorb water, which may cause it to swell and become lodged in narrow areas of the digestive tract (52115).
Genitourinary ...In one clinical trial, some patients reported increased menstrual bleeding while taking a specific ginger extract (Zintoma, Goldaru) 250 mg four times daily orally for 3 days (17931). An "intense" urge to urinate after 30 minutes was reported in two of eight patients given 0.5-1 gram of ginger (7624). However, this effect has not been corroborated elsewhere. Dysuria, flank pain, perineal pain, and urinary stream interruption have been reported in a 43-year-old male who drank ginger tea, containing 2-3 teaspoons of dry ginger, daily over 15 years. The adverse effects persisted for 4 years and were not associated with increases in urinary frequency or urgency. Upon discontinuing ginger, the patient's symptoms began to improve within one week and completely resolved after eight weeks, with no relapses six months later (107902).
Immunologic ...In one case report, a 59-year-old Japanese female with multiple allergic sensitivities developed pruritus and then anaphylactic shock after taking an oral ginger-containing herbal supplement for motion sickness (Keimei Gashinsan, Keimeido). The patient had used this supplement previously for over 20 years with no allergic reaction. The authors theorized the development of a cross-reactivity to ginger after the use of an oral supplement containing zedoary and turmeric, which are also in the Zingiberaceae family (102463).
Neurologic/CNS ...Orally, ginger may cause sedation, drowsiness, or dizziness (16306,17933,51845).
General
...Orally, horny goat weed seems to be well tolerated when used short-term.
Most Common Adverse Effects:
Orally: Dizziness, dry mouth, nosebleed, thirst, and vomiting.
Serious Adverse Effects (Rare):
Orally: Respiratory arrest.
Cardiovascular ...A 66-year-old male with a history of cardiovascular disease developed tachyarrhythmia after taking horny goat weed for 2 weeks (13006). It is not clear if this product contained only horny goat weed or a combination of ingredients; therefore, assigning causality is not possible.
Gastrointestinal ...Orally, long-term use of horny goat weed has been associated with reports of vomiting, dry mouth, thirst, and nosebleed (10346).
Hepatic ...A case of hepatotoxicity characterized by abdominal pain, nausea, vomiting, and fever has been reported in a 40-year-old male patient with hepatitis C, after a month of taking one tablet daily of a combination product containing horny goat weed and multiple other ingredients (Enzyte, Vianda). Symptoms improved following cessation of the product, but it is not clear if they were due to horny goat weed, another ingredients, or hepatitis C (91590). An observational study over 24 years found 26 cases of drug-induced hepatoxicity associated with horny goat weed (112707).
Musculoskeletal ...Orally, large doses of horny goat weed may cause exaggeration of tendon reflexes to the point of spasm (10346).
Neurologic/CNS ...Orally, long-term use of horny goat weed has been associated with reports of dizziness (10346).
Psychiatric ...There is a case report of hypomania in a 66-year-old male who took horny goat weed for 2 weeks (13006). It is not clear if this product contained only horny goat weed or a combination of ingredients; therefore, assigning causality is not possible.
Pulmonary/Respiratory ...Orally, large doses of horny goat weed may cause respiratory arrest (10346).
General
...Orally, kava seems to be well tolerated.
Most Common Adverse Effects:
Orally: Drowsiness, dry mouth, dizziness, gastrointestinal upset, headache, memory problems, tremor.
Serious Adverse Effects (Rare):
Orally: There have been over 100 reported cases of hepatotoxicity and a few reported cases of rhabdomyolysis.
Cardiovascular ...Long-term use of very large amounts of kava, especially in high doses (400 mg kava pyrones daily), has been associated with overall poor health including symptoms of low body weight, reduced protein levels, puffy face, hematuria, increased red blood cell volume, decreased platelets and lymphocytes, and possibly pulmonary hypertension (4032,6402). Tachycardia and electrocardiogram (ECG) abnormalities (tall P waves) have been reported in heavy kava users (6402).
Dermatologic ...Orally, kava can cause allergic skin reactions, including sebotropic eruptions, delayed-type hypersensitivity, or urticarial eruption (4032,11370,28489,57277,57325,57343). Chronic use of high doses of kava has also been associated with kava dermopathy, which consists of reddened eyes; dry, scaly, flaky skin; and temporary yellow discoloration of the skin, hair, and nails (6240,6401,8414,8417,11370,28485,57342). This pellagra-like syndrome is unresponsive to niacinamide treatment (6240,7728,11370). The cause is unknown, but may relate to interference with cholesterol metabolism (6240). Kava's adverse effects on liver function might also contribute to kava dermopathy (6401,8417). Kava dermopathy usually occurs within three months to one year of regular kava use, and resolves when the kava dose is decreased or discontinued (6401,8414). Kava dose should be decreased or discontinued if kava dermopathy occurs (6401).
Gastrointestinal ...Orally, kava may cause gastrointestinal upset, nausea, or dry mouth (2093,2094,4032,11370,18316,57228,57343).
Hematologic ...Orally, chronic use of very high doses of kava has been associated with increased red blood cell volume, reduced platelet volume, reduced lymphocyte counts, and reduced serum albumin (6402,57258). Hematuria has also been reported anecdotally (6402).
Hepatic
...Since the early 2000's, hepatotoxicity has been a particular concern with kava.
Worldwide, there have been at least 100 reported cases of hepatotoxicity following use of kava products (7024,7068,7086,7096,11795,17086)(57252,57254,57297). However, some experts question the clinical validity of several of these cases (11369,11371). Some cases were reported multiple times and in some cases it was unlikely that kava was the causative agent (7068,57253).
In susceptible patients, symptoms can show up after as little as 3-4 weeks of kava use. Symptoms include yellowed skin (jaundice), fatigue, and dark urine (7024,7068). Liver function tests can be elevated after 3-8 weeks of use, possibly followed by hepatomegaly and onset of encephalopathy (7024). Kava has also been reported to exacerbate hepatitis in patients with a history of recurrent hepatitis (390). However, in many cases, symptoms seem to resolve spontaneously, and liver function tests usually normalize within eight weeks (390,7068).
Liver toxicity is more frequently associated with prolonged use of very high doses (6401,57346). But there is some concern that even short-term use of kava in typical doses might cause acute hepatitis in some patients, including severe hepatocellular necrosis. The use of kava for as little as 1-3 months has resulted in need for liver transplant and death, although these events are rare (7024,7068,7086,7096,17086).
There is some speculation that the type of extraction method could be responsible for these rare cases of hepatotoxicity (17086). The "Pacific kava paradox" holds that while the alcohol and acetone extracts of kava used for commercial products cause liver toxicity, the traditional kava rhizome preparation mixed with water might not be toxic (11794,17086). However, a more recent analysis reports cases of hepatotoxicity from the aqueous kava extract and suggests that kava's hepatotoxic effects may be due to contaminants such as mold (29676). Other suggested causes of hepatotoxicity include quality of the kava plant, concomitant medications, large doses and prolonged use, and toxic constituents and metabolites of kava (57300,88532).
Some commercial kava extracts contain parts of the stems and other aerial parts in addition to the rhizome, and it has been suggested that a constituent called pipermethysine, which is only found in these aerial parts, might be partly responsible for hepatotoxicity (17086). Other constituents of kava which might contribute to hepatotoxicity are kavalactones, which are metabolized by cytochrome P450 (CYP450) enzymes in the liver. Reactive metabolites are produced which conjugate with glutathione, and might deplete glutathione in a similar manner to acetaminophen (17086). Increased levels of gamma-glutamyl transferase, involved in the production of glutathione, have been reported in chronic kava users (17086). One of the enzymes involved in production of reactive metabolites from kavalactones is cytochrome P450 2E1 (CYP2E1), which is induced by chronic alcohol intake. Alcohol may also compete for other enzymes which clear kavalactone metabolites from the body. This might explain the observation that alcohol ingestion seems to increase the risk of hepatotoxicity with kava (7068,17086).
There is also speculation that "poor metabolizers" or those patients with deficiency in the cytochrome P450 2D6 (CYP2D6) isoenzyme, which occurs in up to 10% of people of European descent, may be at increased risk for hepatotoxic effects from kava (7068). This deficiency has not been found in Pacific Islanders. However, this theory has not been confirmed.
Due to the concerns regarding the potential hepatotoxicity of kava, kava supplements were withdrawn from European and Canadian markets in 2002 (7086). However, many of the market withdrawals of kava have been lifted after re-evaluation of kava suggested that the risk of hepatotoxicity was minimal (91593,91594,91615). Still, clinical practice guidelines from a joint taskforce of the World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Treatments (CANMAT) recommend exercising caution when using kava in patients with preexisting liver issues (110318). Until more is known, tell patients to use kava cautiously and recommend liver function tests for routine users or those with underlying liver disease.
Immunologic ...Sjögren syndrome has been associated with an herbal supplement containing kava, echinacea, and St. John's wort. Echinacea may have been the primary cause, because Sjögren syndrome is an autoimmune disorder. The role of kava in this syndrome is unclear (10319).
Musculoskeletal
...Kava has been linked with reports of rhabdomyolysis.
A 34-year-old man who consumed kava tea several times a week developed rhabdomyolysis with a peak creatine kinase level of 32,500 units/liter (18212). However, there is speculation that this might have been due to product impurities rather than kava itself. Another case report describes rhabdomyolysis with myoglobinuria and a creatine kinase level of 100,500 units/liter in a 29-year-old man who had taken kava in combination with guarana and ginkgo biloba (18213).
Cases of ataxia and tremors have been reported in patients taking single doses of kava powder 205 grams (11373).
Neurologic/CNS
...Orally, kava may cause headache, dizziness, and drowsiness (4032,6402,11370,11372,11373,18316,112642).
It might also cause extrapyramidal side effects such as involuntary oral and lingual reflexes, twisting movements of the head and trunk, tremors, and other parkinsonian-like symptoms possibly due to dopamine antagonism (534,4055,7727,8415,102086). In one clinical trial, patients taking a kava supplement providing 120 mg of kavalactones twice daily for 16 weeks had a 3.2-fold greater risk of experiencing tremors when compared with patients taking placebo (102086). Theoretically, kava may worsen symptoms in patients with Parkinson disease or precipitate Parkinson-like symptoms in certain patients (4055,7727). Unlike benzodiazepines, kava is not thought to be associated with impaired cognitive function (2097,2098,11373,57332,57333). However, one clinical trial shows that taking a kava supplement providing 120 mg of kavalactones twice daily for 16 weeks increases the risk for memory impairment by 55% when compared with placebo (102086).
Orally, kava may reduce alertness and impair motor coordination in a dose-dependent manner. Some preliminary reports have noted a decline in accuracy of visual attention and slower reaction times after kava ingestion, particularly at higher doses and in combination with alcohol (11373,95926). Population research has also found that ingesting large amounts of kava tea (typically 50 times higher than what is used medicinally in the US) within a 12-hour period before driving increases the odds of being involved in a serious motor vehicle crash resulting in death or serious injury by almost 5-fold when compared to not drinking kava tea (95927). Use of normal doses of kava may also affect the ability to drive or operate machinery, and driving under the influence (DUI) citations have been issued to individuals observed driving erratically after drinking large amounts of kava tea (535). However, in computer-based driving simulator tests, there are no reported adverse effects of kava on performance (95926). Additionally, other research shows that consuming over 4400 mg of kavalactones over a 6-hour kava session does not seem to impair alertness or attention when compared with non-kava drinkers (103867). Similar research using a specific psychometric tool (Brain Gauge) shows that consuming approximately 3680 mg of kavalactones in a 6-hour kava session seems to impair temporal order judgment, which is associated with the brain's ability to track the order of events, when compared with non-kava drinkers. However, it does not seem to impact cognitive domains related to focus, accuracy, timing perception, plasticity, or fatigue when compared with non-kava drinkers (110435).
Ocular/Otic ...Orally, high doses of kava may cause eye irritation (7728). There is one case report of impaired accommodation and convergence, increased pupil diameter, and oculomotor disturbance following a single dose of kava (9920).
Psychiatric ...Apathy has been associated with traditional use of kava at high doses (57313).
Pulmonary/Respiratory ...Orally, kava may cause shortness of breath, possibly due to pulmonary hypertension (6402).
Renal ...Orally, kava may cause acute urinary retention (57349).
General
...Oral, intravenous, and topical L-arginine are generally well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain, bloating, nausea, diarrhea, headache, insomnia, flushing.
Intravenously: Excessively rapid infusion can cause flushing, headache, nausea and vomiting, numbness, and venous irritation.
Cardiovascular ...L-arginine taken orally by pregnant patients in a nutrition bar containing other antioxidants was associated with a 36% greater risk of palpitations when compared with a placebo bar (91197). It is unclear if this effect was due to L-arginine, other ingredients, or other factors.
Dermatologic ...Orally, arginine can cause flushing, rash, and hives (3460,32138,102587,104223). The skin reactions were likely of allergic etiology as oral L-arginine has been associated with eosinophilia (32138). In one case report, intravenous administration caused allergic reactions including urticaria, periorbital edema, and pruritus (11830). Excessively rapid infusion of L-arginine has caused flushing, local venous irritation, numbness. Extravasation has caused necrosis and superficial phlebitis (3330,16817).
Gastrointestinal
...Orally, L-arginine has been reported to cause nausea, diarrhea, vomiting, dyspepsia, gastrointestinal discomfort, and bloating (1363,31855,31871,31972,31978,32261,90198,91197,96811,99243)(102587,102592).
Orally, L-arginine has been reported to cause esophagitis in at least six adolescents. Symptoms, which included pain and dysphagia, occurred within 1-3 months of treatment in most cases (102588). There are at least two cases of acute pancreatitis possibly associated with oral L-arginine. In one case, a 28-year-old male developed pancreatitis after consuming a shake containing 1.2 grams of L-arginine daily as arginine alpha-ketoglutarate. The shake also contained plant extracts, caffeine, vitamins, and other amino acids. Although there is a known relationship between L-arginine and pancreatitis in animal models, it is not clear if L-arginine was directly responsible for the occurrence of pancreatitis in this case (99266).
Intravenously, excessively rapid infusion of L-arginine has been reported to cause nausea and vomiting (3330,16817).
Musculoskeletal ...Intravenous L-arginine has been associated with lower back pain and leg restlessness (32273). Orally, L-arginine has been associated with asthenia (32138).
Neurologic/CNS ...Orally, L-arginine has been associated with headache (31855,31955,32261,91197,102587,102592), insomnia, fatigue (102587,102592), and vertigo (32150,102592).
Oncologic ...In breast cancer patients, L-arginine stimulated tumor protein synthesis, which suggests stimulated tumor growth (31917).
Pulmonary/Respiratory ...When inhaled, L-arginine can cause airway inflammation and exacerbation of airway inflammation in asthma (121). However, two studies assessing oral L-arginine in patients with asthma did not detect any adverse airway effects (31849,104223).
Renal ...Intravenously, L-arginine has been associated with natriuresis, kaliuresis, chloruresis, and systemic acidosis (32225). Orally, L-arginine can cause gout (3331,3595).
Other ...Orally, L-arginine has been associated with delayed menses, night sweats, and flushing (31855).
General
...Orally, Panax ginseng is generally well tolerated when used for up to 6 months.
There is some concern about the long-term safety due to potential hormone-like effects.
Topically, no adverse effects have been reported when ginseng is used as a single ingredient. However, a thorough evaluation of safety outcomes has not been conducted.
Most Common Adverse Effects:
Orally: Insomnia.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis, arrhythmia, ischemia, Stevens-Johnson syndrome.
Cardiovascular ...Panax ginseng may cause hypertension, hypotension, and edema when used orally in high doses, long-term (3353). However, single doses of Panax ginseng up to 800 mg are not associated with changes in electrocardiogram (ECG) parameters or increases in heart rate or blood pressure (96218). There is a case report of menometrorrhagia and tachyarrhythmia in a 39-year-old female who took Panax ginseng 1000-1500 mg/day orally and also applied a facial cream topically that contained Panax ginseng. Upon evaluation for menometrorrhagia, the patient also reported a history of palpitations. It was discovered that she had sinus tachycardia on ECG. However, the patient was a habitual consumer of coffee 4-6 cups/day and at the time of evaluation was also mildly anemic. The patient was advised to discontinue taking Panax ginseng. During the 6 month period following discontinuation the patient did not have any more episodes of menometrorrhagia or tachyarrhythmia (13030). Also, a case of transient ischemic attack secondary to a hypertensive crisis has been reportedly related to oral use of Panax ginseng (89402).
Dermatologic
...Orally, Panax ginseng may cause itching or an allergic response consisting of systemic rash and pruritus (89743,89760,104953).
Skin eruptions have also been reported with use of Panax ginseng at high dosage, long-term (3353). Uncommon side effects with oral Panax ginseng include Stevens-Johnson syndrome (596).
In one case report, a 6-year-old male with a previous diagnosis of generalized pustular psoriasis, which had been in remission for 18 months, presented with recurrent pustular lesions after consuming an unspecified dose of Panax ginseng. The patient was diagnosed with pityriasis amiantacea caused by subcorneal pustular dermatosis. Treatment with oral dapsone 25 mg daily was initiated, and symptoms resolved after 4 weeks (107748).
Topically, when a specific multi-ingredient cream preparation (SS Cream) has been applied to the glans penis, mild pain, local irritation, and burning have occurred (2537).
Endocrine
...The estrogenic effects of ginseng are controversial.
Some clinical evidence suggests it doesn't have estrogen-mediated effects (10981). However, case reports of ginseng side effects such as postmenopausal vaginal bleeding suggest estrogenic activity (590,591,592,10982,10983).
In a 12-year-old Korean-Japanese male, enlargement of both breasts with tenderness in the right breast (gynecomastia) occurred after taking red ginseng extract 500 mg daily orally for one month. Following cessation of the product, there was no further growth or pain (89733). Swollen and tender breasts also occurred in a 70-year-old female using Panax ginseng orally (590).
Gastrointestinal ...Orally, Panax ginseng can cause decreased appetite (3353), diarrhea (3353,89734,103477), abdominal pain (89734,87984), and nausea (589,87984). However, these effects are typically associated with long-term, high-dose usage (3353).
Genitourinary
...Amenorrhea has been reported with oral use of Panax ginseng (3353).
Topically, when a specific multi-ingredient cream preparation (SS Cream) has been applied to the glans penis, sporadic erectile dysfunction and excessively delayed ejaculation have occurred (2537). Less commonly, patients can experience vaginal bleeding (591,592,3354,23630).
Hepatic ...Uncommon side effects can include cholestatic hepatitis (associated with a Panax ginseng-containing, multi-ingredient product, Prostata), such as that which occurred in a 65-year old male following oral use (598).
Immunologic ...A case of anaphylaxis, with symptoms of hypotension and rash, has been reported following ingestion of a small amount of Panax ginseng syrup (11971).
Neurologic/CNS ...Orally, one of the most common side effects to Panax ginseng is insomnia (589,89734). Headache (594,23638), vertigo, euphoria, and mania (594) have also been reported. Migraine and somnolence occurred in single subjects in a clinical trial (87984). In a case report of a 46-year-old female, orobuccolingual dyskinesia occurred following oral use of a preparation containing black cohosh 20 mg and Panax ginseng 50 mg twice daily for menopausal symptoms. The patient's condition improved once the product was stopped and treatment with baclofen 40 mg and clonazepam 20 mg daily was started (89735).
General
...Orally, tribulus seems to be well tolerated.
Serious Adverse Effects (Rare):
Orally: Cases of liver and kidney injury, seizures, and chronic painful erection with impaired sexual function have been reported. Pneumothorax and bronchial polyp after consuming the spine-covered tribulus fruit have been reported.
Gastrointestinal ...Orally, tribulus can cause abdominal pain, cramping, nausea, vomiting, diarrhea, and constipation (92022,92027). However, in one study, the rates of these gastrointestinal complaints were similar for patients taking tribulus and those receiving placebo (92022).
Genitourinary ...In one case report, a patient taking two tribulus tablets (unknown dose) daily for 15 days presented to the local emergency department with a painful erection lasting 72 hours. The priapism was resolved with medical management; however, post-episode sexual function was impaired (92023).
Hepatic ...In one case report, a patient drinking tribulus water 2 liters daily for two days presented with lower limb weakness, seizures, hepatitis, and acute kidney injury. The patient's condition improved after hemodialysis and discontinuation of tribulus water (92069).
Neurologic/CNS ...Orally, tribulus has been reported to cause general excitation and insomnia. These symptoms were reversed upon discontinuation of the drug or decreasing the dose (78867). In one case report, a patient drinking tribulus water 2 liters daily for two days presented with lower limb weakness, seizures, hepatitis, and acute kidney injury. The patient's condition improved after hemodialysis and discontinuation of tribulus water (92069).
Pulmonary/Respiratory ...In one case report, a patient developed a bilateral pneumothorax after consuming the spine-covered fruit of tribulus (818). In another case report, a patient developed a polyp in the lobar bronchus of the right interior lobe due to the presence of a tribulus fruit spine (78852).
Renal ...In one case report, a patient drinking tribulus water 2 liters daily for two days presented with lower limb weakness, seizures, hepatitis, and acute kidney injury. The patient's condition improved after hemodialysis and discontinuation of the tribulus water (92069). In another case report, a healthy male taking one tribulus tablet (unknown dose) daily for a few months for bodybuilding purposes developed hyperbilirubinemia followed by acute kidney failure 2-3 weeks later. The patient was managed with intravenous fluids and a low-salt, low-protein diet (92025).
Other ...In one case report, gynecomastia was observed in a male weightlifter taking an herbal combination product containing tribulus. However, it is not clear if this adverse effect can be attributed to tribulus alone (78859).
General
...Orally, vitex agnus-castus is generally well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, fatigue, headache, insomnia, irregular menstruation, nausea, skin irritation, stomach pain, vomiting.
Dermatologic ...Orally, skin conditions such as itching, irritation, urticaria, rash, acne, eczema, and hair loss have been reported (7055,7076,7078,7079,12207,13393,15065,90617,90619,101981).
Gastrointestinal ...Orally, gastrointestinal upset or pain, diarrhea, and nausea and vomiting, have been reported (7079,12207,13393,15065,90620,101981,101982). In one clinical trial, a single patient reported persistent gastroenteritis while taking vitex agnus-castus (7076). Orally, development of a bezoar resulting in colonic obstruction is described in a 63-year-old male who consumed an unknown amount of vitex agnus-castus seeds (111752).
Genitourinary ...Orally, irregular or prolonged menstrual bleeding has been reported (7055,7079,12207,13393,15065,41489,41490,95326).
Hematologic ...Orally, nosebleed has been reported in a single patient in a clinical trial (7079).
Immunologic ...Orally, multiple abscesses have been reported in a single patient (7055).
Neurologic/CNS ...Orally, headache, fatigue, and insomnia (7076,7078,12207,13393,13395,15065), confusion (90617), and vertigo (7079) have been reported.
Other ...Orally, weight gain has been reported (12207,13393,15065).
