American Ginseng rt • Ginkgo biloba lf • Gotu Kola hb • Valerian rt.
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Below is general information about the effectiveness of the known ingredients contained in the product Natural Attention Aid. 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
Below is general information about the safety of the known ingredients contained in the product Natural Attention Aid. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
LIKELY SAFE ...when used orally and appropriately, short-term. American ginseng 100-3000 mg daily has been safely used for up to 12 weeks (1018,4225,4236,6461,9732,14804,19552,22367,22368)(22369,22370). Single doses up to 10 grams have also been safely used (6461,89404). A specific American ginseng extract called CVT-E002 (Cold-FX, Afexa Life Sciences) has also been used safely for up to 64 months (11351,13192,14345,91275).
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
A specific American ginseng extract called CVT-E002 (Cold-FX, Afexa Life Sciences) in doses of 4.5-26 mg daily for 3 days has been used with apparent safety in children aged 3-12 years (22365).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Ginsenoside Rb1, an active constituent of American ginseng, has teratogenic effects in animal models (10447); avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally and appropriately. Standardized ginkgo leaf extracts have been used safely in trials lasting for several weeks up to 6 years (1514,1515,3461,5717,5718,6211,6212,6213,6214,6215)(6216,6222,6223,6224,6225,6490,14383,14499,16634,16635)(16636,16637,17402,17716,17718,87794,87819,87826,87848,87864)(87888,87897,87901,87904,89701,89707,107359,107360). There have been some reports of arrhythmias associated with ginkgo leaf extract. However, it is not yet clear if ginkgo might cause arrhythmia (105253,105254). There is some concern about toxic and carcinogenic effects seen in animals exposed to a ginkgo leaf extract containing 31.2% flavonoids, 15.4% terpenoids, and 10.45 ppm ginkgolic acid, in doses of 100 to 2000 mg/kg five times per week for 2 years (18272). However, the clinical relevance of this data for humans, using typical doses, is unclear. The content of the extract used is not identical to that commonly used in supplement products, and the doses studied are much higher than those typically used by humans. A single dose of 50 mg/kg in rats is estimated to be equivalent to a single dose of about 240 mg in humans (18272).
POSSIBLY SAFE ...when used intravenously, short-term. A standardized ginkgo leaf extract called EGb 761 ONC has been safely administered intravenously for up to 14 days (9871,9872,107360,107452). A Chinese preparation containing ginkgo leaf extract and dipyridamole has been safely administered intravenously for up to 30 days (102881,102882). ...when applied topically, short-term. There was no dermal irritation during a 24-hour patch test using the leaf extract, and no sensitization with repeat applications (112946). When used topically in cosmetics, extracts of ginkgo leaves are reported to be safe, but there is insufficient data to determine the safety of nut and root extracts, and isolated biflavones and terpenoids (112946).
POSSIBLY UNSAFE ...when the roasted seed or crude ginkgo plant is used orally. Consuming more than 10 roasted seeds per day can cause difficulty breathing, weak pulse, seizures, loss of consciousness, and shock (8231,8232). Crude ginkgo plant parts can exceed concentrations of 5 ppm of the toxic ginkgolic acid constituents and can cause severe allergic reactions (5714).
LIKELY UNSAFE ...when the fresh ginkgo seed is used orally. Fresh seeds are toxic and potentially deadly (11296).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
There is concern that ginkgo might have labor-inducing and hormonal effects. There is also concern that the antiplatelet effects of ginkgo could prolong bleeding time if taken around the time of labor and delivery (15052). Theoretically, ginkgo might adversely affect pregnancy outcome; avoid using during pregnancy.
LACTATION:
Insufficient reliable information available; avoid using.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term (87790,89708).
A specific ginkgo dried extract (Ginko T.D., Tolidaru Pharmaceuticals), has been safely used in doses of 80-120 mg daily for 6 weeks in children aged 6-14 years (17112,95669). Another specific combination product containing ginkgo leaf extract and American ginseng extract (AD-FX, CV Technologies, Canada) has also been safely used in children aged 3-17 years for up to 4 weeks (8235).
CHILDREN: LIKELY UNSAFE
when ginkgo seed is used orally.
The fresh seeds have caused seizures and death in children (8231,11296).
POSSIBLY SAFE ...when used topically and appropriately. Gotu kola has been used safely in a cream or ointment for up to 10 weeks (11072,11073,67372,102792,105329,105335). An emulsion containing gotu kola extract 3% and other ingredients has been applied safely to the skin twice daily for up to 60 days (111571). ...when used orally and appropriately. Gotu kola extract has been used with apparent safety in doses of up to 180 mg daily for up to 12 months or 1000 mg daily for 60 days. Dried gotu kola has been used with apparent safety in doses of up to 2200 mg daily for 4 weeks (6887,11062,11063,11064,11065,11066,11067,11068,11069,11070)(11071,99756,99757,99758,105329,105332,105333). A specific gotu kola extract (Centellicum, Horphag Research Ltd) 450-675 mg daily has been used with apparent safety for up to 6 weeks (99756,99757).
PREGNANCY: POSSIBLY SAFE
when used topically and appropriately (11073,13559).
There is insufficient reliable information available about the safety gotu kola when used orally during pregnancy; avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally and appropriately, short-term. Valerian 300-600 mg daily has been safely used in clinical studies in over 12,000 patients for up to 6 weeks (2074,3484,3485,4032,15018,17577,17578,19409,96242,103221)(104010,105718). There is insufficient reliable information available about the safety of valerian when used orally for longer than 6 weeks.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
Valerian 160-320 mg has been used with apparent safety in children under 12 years of age for 4-8 weeks (14416).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
Below is general information about the interactions of the known ingredients contained in the product Natural Attention Aid. 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 American ginseng with antidiabetes drugs might increase the risk of hypoglycemia.
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Theoretically, American ginseng use might interfere with immunosuppressive therapy.
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Theoretically, American ginseng can interfere with MAOI therapy.
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There is one case report of insomnia, headache, and tremors when an unspecified ginseng product was used with phenelzine (Nardil), an MAOI (617). There is also one case report of hypomania when an unspecified ginseng product was used with phenelzine (618). Theoretically, American ginseng may interfere with MAOI therapy.
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American ginseng seems to decrease the effectiveness of warfarin therapy.
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Theoretically, ginkgo might decrease the levels and clinical effects of alprazolam.
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In clinical research, ginkgo extract (Ginkgold) 120 mg twice daily seems to decrease alprazolam levels by about 17%. However, ginkgo does not appear to decrease the elimination half-life of alprazolam. This suggests that ginkgo is more likely to decrease absorption of alprazolam rather than induce hepatic metabolism of alprazolam (11029).
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Ginkgo has been shown to increase the risk of bleeding in some people when taken with warfarin. Theoretically, ginkgo might increase the risk of bleeding if used with other anticoagulant or antiplatelet drugs.
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Several pharmacodynamic studies suggest that ginkgo inhibits platelet aggregation. It is thought that the ginkgo constituent, ginkgolide B, displaces platelet-activating factor (PAF) from its binding sites, decreasing blood coagulation (6048,9760). Several case reports have documented serious bleeding events in patients taking ginkgo (244,578,579,8581,13002,13135,13179,13194,14456,87868). However, population and clinical studies have produced mixed results. Some evidence shows that short-term use of ginkgo leaf does not significantly reduce platelet aggregation and blood clotting (87732). A study in healthy males who took a specific ginkgo leaf extract (EGb 761) 160 mg twice daily for 7 days found no change in prothrombin time (12114). An analysis of a large medical record database suggests that ginkgo increases the risk of a bleeding adverse event by 38% when taken concurrently with warfarin (91326). It has been suggested that ginkgo has to be taken for at least 2-3 weeks to have a significant effect on platelet aggregation (14811). However, a meta-analysis of 18 studies using standardized ginkgo extracts, 80-480 mg daily for up to 32 weeks, did not find a significant effect on platelet aggregation, fibrinogen concentration, or PT/aPTT (17179). In addition, a single dose of ginkgo plus clopidogrel (14811) or ticlopidine does not seem to significantly increase bleeding time or platelet aggregation (17111,87846). Also, taking ginkgo leaf extract daily for 8 days in conjunction with rivaroxaban does not affect anti-factor Xa activity; however, this study did not evaluate bleeding time (109526).
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Theoretically, ginkgo might reduce the effectiveness of anticonvulsants.
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Ginkgo seeds contain ginkgotoxin. Large amounts of ginkgotoxin can cause neurotoxicity and seizure. Ginkgotoxin is present in much larger amounts in ginkgo seeds than leaves (8232). Ginkgo leaf extract contains trace amounts of ginkgotoxin. The amount of ginkgotoxin in ginkgo leaf and leaf extract seems unlikely to cause toxicity (11296). However, there are anecdotal reports of seizure occurring after use of ginkgo leaf both in patients without a history of seizure disorder and in those with previously well-controlled epilepsy (7030,7090).
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Theoretically, taking ginkgo with antidiabetes drugs might alter the response to antidiabetes drugs.
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Ginkgo leaf extract seems to alter insulin secretion and metabolism, and might affect blood glucose levels in people with type 2 diabetes (5719,14448,103574). The effect of ginkgo seems to differ depending on the insulin and treatment status of the patient. In diet-controlled diabetes patients with hyperinsulinemia, taking ginkgo does not seem to significantly affect insulin or blood glucose levels. In patients with hyperinsulinemia who are treated with oral hypoglycemic agents, taking ginkgo seems to decrease insulin levels and increase blood glucose following an oral glucose tolerance test. Researchers speculate that this could be due to ginkgo-enhanced hepatic metabolism of insulin. In patients with pancreatic exhaustion, taking ginkgo seems to stimulate pancreatic beta-cells, resulting in increased insulin and C-peptide levels, but with no significant change in blood glucose levels in response to an oral glucose tolerance test (14448).
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Theoretically, ginkgo might decrease the levels and clinical effects of atorvastatin.
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In humans, intake of ginkgo extract appears to increase atorvastatin clearance, reducing the area under the curve of atorvastatin by 10% to 14% and the maximum concentration by 29%. However, this interaction does not appear to affect cholesterol synthesis and absorption (89706). Further, a model in rats with hyperlipidemia suggests that administering ginkgo extract does not impact blood levels of atorvastatin and leads to lower total cholesterol, low-density lipoprotein cholesterol, and triglycerides when compared with rats given atorvastatin alone (111331).
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Theoretically, ginkgo might increase levels of drugs metabolized by CYP1A2.
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Theoretically, ginkgo might decrease levels of drugs metabolized by CYP2C19.
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Some clinical research shows that a specific ginkgo leaf extract (Remembrance, Herbs Product LTD) 140 mg twice daily can induce CYP2C19 enzymes and potentially decrease levels of drugs metabolized by these enzymes (13108). However, other clinical research shows that taking ginkgo 120 mg twice daily for 12 days has no effect on levels of drugs metabolized by CYP2C19 (87824).
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Theoretically, ginkgo might increase levels of drugs metabolized by CYP2C9.
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In vitro, a specific standardized extract of ginkgo leaf (EGb 761) inhibits CYP2C9 activity (11026,12061,14337). The terpenoid (ginkgolides) and flavonoid (quercetin, kaempferol, etc.) constituents seem to be responsible for this effect. Most ginkgo extracts contain some amount of these constituents. Therefore, other ginkgo leaf extracts might also inhibit the CYP2C9 enzyme. However, clinical research suggests that ginkgo might not have a significant effect on CYP2C9 in humans. Ginkgo does not seem to significantly affect the pharmacokinetics of CYP2C9 substrates diclofenac or tolbutamide.
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Theoretically, ginkgo might decrease levels of drugs metabolized by CYP3A4.
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There is conflicting evidence about whether ginkgo induces or inhibits CYP3A4 (1303,6423,6450,11026,87800,87805,111330). Ginkgo does not appear to affect hepatic CYP3A4 (11029). However, it is not known if ginkgo affects intestinal CYP3A4. Preliminary clinical research suggests that taking ginkgo does not significantly affect levels of donepezil, lopinavir, or ritonavir, which are all CYP3A4 substrates (11027,87800,93578). Other clinical research also suggests ginkgo does not significantly affect CYP3A4 activity (10847). However, there are two case reports of decreased efavirenz concentrations and increased viral load in patients taking ginkgo. It is suspected that terpenoids from the ginkgo extract reduced drug levels by inducing cytochrome P450 3A4 (CYP3A4) (16821,25464).
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Theoretically, ginkgo might decrease the levels and clinical effects of efavirenz.
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There are two case reports of decreased efavirenz concentrations and increased viral load in patients taking ginkgo. In one case, an HIV-positive male experienced over a 50% decrease in efavirenz levels over the course of 14 months while taking ginkgo extract. HIV-1 RNA copies also increased substantially, from less than 50 to more than 1500. It is suspected that terpenoids from the ginkgo extract reduced drug levels by inducing cytochrome P450 3A4 (CYP3A4) (16821). In another case report, a patient stable on antiviral therapy including efavirenz for 10 years, had an increase in viral load from <50 copies/mL to 1350 copies/mL after 2 months of taking a combination of supplements including ginkgo. After stopping ginkgo, the viral load was again controlled with the same antiviral therapy regimen (25464).
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Theoretically, ginkgo might increase the risk of bleeding when used with ibuprofen.
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Ginkgo might have antiplatelet effects and has been associated with several case reports of spontaneous bleeding. In one case, a 71-year-old male had taken a specific ginkgo extract (Gingium, Biocur) 40 mg twice daily for 2.5 years. About 4 weeks after starting ibuprofen 600 mg daily he experienced a fatal intracerebral hemorrhage (13179). However, the antiplatelet effects of ginkgo have been questioned. A meta-analysis and other studies have not found a significant antiplatelet effect with standardized ginkgo extracts, 80 mg to 480 mg taken daily for up to 32 weeks (17179).
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Theoretically, taking ginkgo with oral, but not intravenous, nifedipine might increase levels and adverse effects of nifedipine.
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Animal research and some clinical evidence suggests that taking ginkgo leaf extract orally in combination with oral nifedipine might increase nifedipine levels and cause increased side effects, such as headaches, dizziness, and hot flushes (87764,87765). However, taking ginkgo orally does not seem to affect the pharmacokinetics of intravenous nifedipine (87765).
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Theoretically, taking ginkgo with omeprazole might decrease the levels and clinical effects of omeprazole.
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Clinical research shows that a specific ginkgo leaf extract (Remembrance, Herbs Product LTD) 140 mg twice daily can induce cytochrome P450 (CYP) 2C19 enzymes and decrease levels of omeprazole by about 27% to 42% (13108).
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Theoretically, taking ginkgo with P-glycoprotein substrates might increase the levels and adverse effects of these substrates.
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A small clinical study in healthy volunteers shows that using ginkgo leaf extract 120 mg orally three times daily for 14 days can increase levels of the P-glycoprotein substrate, talinolol, by 36% in healthy male individuals. However, single doses of ginkgo do not have the same effect (87830).
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Theoretically, taking ginkgo with risperidone might increase the levels and adverse effects of risperidone.
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A single case of priapism has been reported for a 26-year-old male with schizophrenia who used risperidone 3 mg daily along with ginkgo extract 160 mg daily (87796). Risperidone is metabolized by cytochrome P450 (CYP) 2D6 and CYP3A4. CYP3A4 activity might be affected by ginkgo. Theoretically, ginkgo may inhibit the metabolism of risperidone and increase the risk of adverse effects.
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Theoretically, ginkgo might decrease the levels and clinical effects of rosiglitazone.
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Animal research shows that ginkgo leaf extract orally 100 or 200 mg/kg daily for 10 days alters the pharmacodynamics of rosiglitazone in a dose-dependent manner. The 100 mg/kg and 200 mg/kg doses reduce the area under the concentration time curve (AUC) of rosiglitazone by 39% and 52%, respectively, and the half-life by 28% and 39%, respectively. It is hypothesized that these changes may be due to induction of cytochrome P450 2C8 by ginkgo (109525).
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Theoretically, taking ginkgo with drugs that lower the seizure threshold might increase the risk for convulsions.
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Ginkgo seeds contain ginkgotoxin. Large amounts of ginkgotoxin can cause neurotoxicity and seizure. Ginkgotoxin is present in much larger amounts in ginkgo seeds than leaves (8232). Ginkgo leaf extract contains trace amounts of ginkgotoxin. The amount of ginkgotoxin in ginkgo leaf and leaf extract seems unlikely to cause toxicity (11296). However, there are anecdotal reports of seizure occurring after use of ginkgo leaf both in patients without a history of seizure disorder and in those with previously well-controlled epilepsy (7030,7090,14281).
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Theoretically, ginkgo might decrease the levels and clinical effects of simvastatin.
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Clinical research shows that taking ginkgo extract can reduce the area under the curve and maximum concentration of simvastatin by 32% to 39%. However, ginkgo extract does not seem to affect the cholesterol-lowering ability of simvastatin (89704).
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Theoretically, ginkgo might increase the levels and clinical effects of sofosbuvir.
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Animal research in rats shows that giving a ginkgo extract 25 mg/kg orally daily for 14 days increases the area under the concentration time curve (AUC) after a single sofosbuvir dose of 40 mg/kg by 11%, increases the half-life by 60%, and increases the plasma concentration at 4 hours by 38%. This interaction appears to be related to the inhibition of intestinal P-glycoprotein by ginkgo (109524).
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Theoretically, ginkgo might increase the blood levels of tacrolimus.
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In vitro evidence suggests that certain biflavonoids in ginkgo leaves (i.e. amentoflavone, ginkgetin, bilobetin) may inhibit the metabolism of tacrolimus by up to 50%. This interaction appears to be time-dependent and due to inhibition of cytochrome P450 (CYP) 3A4 by these bioflavonoids. In rats given tacrolimus 1 mg/kg orally, amentoflavone was shown to increase the area under the concentration time curve (AUC) of tacrolimus by 3.8-fold (111330).
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Taking ginkgo with talinolol seems to increase blood levels of talinolol.
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There is some evidence that using ginkgo leaf extract 120 mg orally three times daily for 14 days can increase levels of talinolol by 36% in healthy male individuals. However, single doses of ginkgo do not seem to affect talinolol pharmacokinetics (87830).
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Theoretically, ginkgo might increase the levels and clinical effects of trazodone.
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In a case report, an Alzheimer patient taking trazodone 20 mg twice daily and ginkgo leaf extract 80 mg twice daily for four doses became comatose. The coma was reversed by administration of flumazenil (Romazicon). Coma might have been induced by excessive GABA-ergic activity. Ginkgo flavonoids are thought to have GABA-ergic activity and act directly on benzodiazepine receptors. Ginkgo might also increase metabolism of trazodone to active GABA-ergic metabolites, possibly by inducing cytochrome P450 3A4 (CYP3A4) metabolism (6423).
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Ginkgo has been shown to increase the risk of bleeding in some people when taken with warfarin.
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Several pharmacodynamic studies suggest that ginkgo inhibits platelet aggregation. It is thought that the ginkgo constituent, ginkgolide B, displaces platelet-activating factor (PAF) from its binding sites, decreasing blood coagulation (6048,9760). Several case reports have documented serious bleeding events in patients taking ginkgo (244,576,578,579,8581,13002,13135,13179,13194,14456,87868). Information from a medical database suggests that when taken concurrently with warfarin, ginkgo increases the risk of a bleeding adverse event by 38% (91326). There is also some evidence that ginkgo leaf extract can inhibit cytochrome P450 2C9, an enzyme that metabolizes warfarin. This could result in increased warfarin levels (12061). However, population and clinical research has produced mixed results. Clinical research in healthy people suggests that ginkgo has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin (12881,15176,87727,87889). A meta-analysis of 18 studies using standardized ginkgo extracts, 80 mg to 480 mg daily for up to 32 weeks, did not find a significant effect on platelet aggregation, fibrinogen concentration, or PT/aPTT (17179). There is also some preliminary clinical research that suggests ginkgo might not significantly increase the effects of warfarin in patients that have a stable INR (11905).
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Theoretically, taking gotu kola might increase the sedative effects of CNS depressants.
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Theoretically, taking gotu kola with hepatotoxic drugs might have additive adverse effects.
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Valerian can have additive sedative effects when used concomitantly with alcohol.
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Valerian has sedative effects (9894). Theoretically, valerian might have an additive sedative effect when combined with alcohol. Excessive sedation has been reported in an alcohol-abusing individual who took valerian and Gingko biloba (19426). However, the potential interaction between valerian and alcohol has been disputed in other research. Limited evidence suggests that a combination of valerian 160 mg and lemon balm 80 mg (Euvegal) does not cause further deterioration in reaction ability and reaction rate when taken with alcohol as compared to the effects of alcohol alone (19427).
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Valerian can have additive sedative effects when used with alprazolam. Also, valerian in high doses might modestly increase alprazolam levels, though this is not likely to be clinically significant.
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Valerian has sedative effects (9894). Theoretically, valerian might cause additive sedation when combined with alprazolam. Also, a small pharmacokinetic study shows that taking valerian extract 1000 mg daily (providing 11 mg valerenic acid) might increase alprazolam levels by about 19%. This might be due to valerian's mild inhibition of cytochrome P450 3A4 (CYP3A4) (13014). Despite being statistically significant, this increase is not likely to be clinically significant.
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Valerian can have additive sedative effects when used concomitantly with CNS depressant drugs.
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Valerian does not seem to have a clinically relevant effect on levels of drugs metabolized by CYP2D6.
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Although some in vitro evidence suggests that valerian affects CYP2D6, clinical pharmacokinetic (PK) studies show that valerian is unlikely to affect the CYP2D6 enzyme (13014,13536,19430,19431). In one PK study, taking valerian 1000 mg (providing about 11 mg valerenic acid) nightly for 14 days did not affect the metabolism of dextromethorphan, a CYP2D6 substrate. In another PK study, taking valerian 125 mg three times daily for 28 days did not affect metabolism of debrisoquine, an accepted CYP2D6 probe-substrate (13014,13536).
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Valerian does not seem to have a clinically relevant effect on levels of drugs metabolized by CYP3A4.
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Although some in vitro evidence suggests that valerian extract might inhibit or induce CYP3A4, clinical pharmacokinetic (PK) studies show that valerian does not have a clinically significant effect on the CYP3A4 enzyme (6450,12214,13014,13536,19431). In one PK study, taking valerian 125 mg three times daily for 28 days did not affect metabolism of midazolam, an accepted CYP3A4 probe-substrate. In another PK study, taking valerian 1000 mg (providing about 11 mg valerenic acid) nightly for 14 days modestly increases levels of alprazolam, a CYP3A4 substrate, suggesting mild inhibition of CYP3A4 (13014,13536). However, this mild inhibition is unlikely to be clinically relevant.
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Valerian might weakly inhibit glucuronidation and increase concentrations of drugs metabolized by UGT1A1 and UGT2B7.
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In vitro research shows that methanolic valerian extract and valerenic acid might competitively inhibit UDP-glucuronosyltransferase (UGT) 1A1 (UGT1A1) and UGT2B7 (81685).
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Below is general information about the adverse effects of the known ingredients contained in the product Natural Attention Aid. 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, ginkgo leaf extract is generally well tolerated when used for up to 6 years.
However, the seed and crude plant contain toxic constituents and should be avoided.
Intravenously, ginkgo leaf extract seems to be well tolerated when used for up to 30 days.
Topically, no adverse effects have been reported with ginkgo as a single ingredient. However, a thorough evaluation of safety outcomes has not been conducted.
Most Common Adverse Effects:
Orally: Dizziness, gastrointestinal symptoms, headache.
Serious Adverse Effects (Rare):
Orally: Arrhythmia, bleeding, Stevens-Johnson syndrome.
Cardiovascular
...Cardiac arrhythmias suspected to be related to ginkgo have been reported.
Internationally, there are at least 162 reports from 18 countries, with 34% of cases considered serious, involving five deaths and four life-threatening events. Additionally, a report from Canada found that 10 out of 15 cases of arrhythmia were considered serious. Ginkgo was the only suspect ingredient in 57% of all international reports, with symptoms generally presenting within days of initiation. The most common symptoms included palpitations, tachycardia, bradycardia, syncope, and loss of consciousness. Most cases were reported to be related to oral use of ginkgo leaf products; however, some cases were associated with oral use of the seed, and others with intravenous or intramuscular use of the leaf. Documented discontinuation of ginkgo led to recovery in approximately 84% of cases where ginkgo was the sole suspect. Despite these findings, ginkgo cannot be confirmed as the causal agent. It is possible that these reports are confounded by underlying co-morbidities. Of the reported cases, the main reason for ginkgo use was tinnitus, a symptom commonly associated with pre-existing arrhythmias (105253,105254). Despite this large number of reports, only three cases of cardiac arrhythmia have been published in the literature (105253,105254). In one case, frequent nocturnal episodes of paroxysmal atrial fibrillation were reported for a 35-year-old female taking ginkgo extract 240 mg daily orally for 2 months. Arrythmias ceased following discontinuation of ginkgo (87884).
In one clinical trial, the rate of ischemic stroke and transient ischemic attacks was significantly higher in patients taking ginkgo extract orally when compared with placebo (16635). It is unclear if these events were due to ginkgo, other factors, or a combination.
Dermatologic ...Topically, ginkgo fruit pulp can cause contact dermatitis, with intense itching, edema, papules, and pustules which take 7-10 days to resolve after stopping contact (112946).
Gastrointestinal
...Orally, ginkgo extract may cause mild gastrointestinal discomfort or pain (3965,8543,17112,87818,87858), nausea and vomiting (8543,17112,87728,87844,87858), diarrhea (87844), dry mouth (17112), and constipation (5719,87787).
However, post-market surveillance suggests that the incidence of these events is relatively low, occurring in less than 2% of patients (88007).
Fresh ginkgo seeds can cause stomach ache, nausea, vomiting, or diarrhea. Ingesting roasted seeds in amounts larger than the normal food amounts of 8-10 seeds per day, or long-term, can also cause these same adverse reactions (8231,8232).
Genitourinary ...Orally, ginkgo extract has been reported to cause blood in the urine in one patient (87858).
Hematologic
...Spontaneous bleeding is one of the most concerning potential side effects associated with ginkgo.
There are several published case reports linking ginkgo to episodes of minor to severe bleeding; however, not all case reports clearly establish ginkgo as the cause of bleeding. In most cases, other bleeding risk factors were also present including taking other medications or natural medicines, old age, liver cirrhosis, recent surgery, and other conditions. In most cases, bleeding occurred after several weeks or months of taking ginkgo (13135). Large-scale clinical trials and a meta-analysis evaluating standardized ginkgo leaf extracts show that the incidence of bleeding in patients taking ginkgo is not significantly higher than in those taking placebo (16634,16635,17179,17402).
There are several case reports of intracerebral bleeding. Some of these cases resulted in permanent neurological damage and one case resulted in death (244,578,8581,13135,13179,14456,87868,87977).
There are at least 4 cases of ocular bleeding including spontaneous hyphema (bleeding from the iris into the anterior part of the eye) and retrobulbar hemorrhage associated with ginkgo use (579,10450,13135).
There are also cases of surgical and post-surgical complications in patients using ginkgo. Retrobulbar hemorrhage (bleeding behind the eye) during cataract surgery has been associated with ginkgo use (10450). Excessive postoperative bleeding requiring transfusion has also occurred following laparoscopic surgery in a patient who had been taking ginkgo leaf extract (887). There have also been two cases of excessive bleeding during surgery and post-surgical hematoma in patients undergoing rhytidoplasty and blepharoplasty (13002). In another case, an elderly patient taking ginkgo experienced excessive postoperative bleeding following total hip arthroplasty (13194). In another case, use of ginkgo following liver transplantation surgery was associated with subphrenic hematoma requiring evacuation by laparotomy. The patient also subsequently experienced vitreous hemorrhage (14315). In another case, an elderly patient who had taken ginkgo chronically experienced excessive post-operative bleeding following an ambulatory surgical procedure (14453).
In another case, an elderly man experienced nose bleeds and ecchymosis following use of ginkgo. One case of diffuse alveolar hemorrhage in a female taking ginkgo and ginseng for over one year has been reported (95670). These instances of bleeding stopped when ginkgo was discontinued, and recurred when the patient started taking ginkgo again (13135).
Persistent bleeding has also occurred following dental surgery (87862) and laparoscopic cholecystectomy (88000). Nosebleed has also been reported as an adverse effect in a clinical trial (87813).
Immunologic ...Orally, ginkgo leaf extract can cause allergic skin reactions in some patients (14449,15578,112946). In one case, a patient developed acute generalized exanthematous pustulosis 48 hours after taking a single-ingredient ginkgo product. The rash resolved within 10 days after discontinuing ginkgo (14449). In another case, progressive erythema of the face, neck, trunk, and extremities occurred after two 60 mg oral doses of ginkgo extract (112946). There is also a case of Stevens-Johnson syndrome following a second administration of a preparation containing ginkgo leaf extract, choline, vitamin B6, and vitamin B12 (208). In another case, systemic edema and severe arthralgia was reported after contact with a ginkgo tree nut and manifested as multifocal lymphadenopathy associated with an allergic reaction on PET/CT scan imaging (95672).
Musculoskeletal ...Edema has been reported for three patients treated with ginkgo extract 40 mg orally three times daily (87818).
Neurologic/CNS ...Orally, ginkgo extract may cause headache (6220,8543,87818), dizziness (5719,87818), increased desire to sleep (87839), and sedation (10893) in some patients. In addition, although ginkgo leaf and ginkgo leaf extract contain only small amounts of ginkgotoxin, there are anecdotal reports of seizure occurring after use of ginkgo leaf preparations both in patients without a history of seizure disorder and in those with previously well-controlled epilepsy (7030,7090,11296,14281).
Ocular/Otic
...Orally, ginkgo extract may cause tinnitus is some patients, although the incidence is rare (8543).
Topically, eye drops containing ginkgo extract and hyaluronic acid may cause stinging sensations in some people (87829).
Psychiatric ...Orally, ginkgo has been associated with a single case of mood dysregulation. A 50-year-old female with schizophrenia developed irritability, difficulty controlling anger, and agitation after one week of taking ginkgo 80 mg twice daily. The mood changes resolved within 2-3 days of discontinuation. When ginkgo was re-trialed at a later date, the same symptoms reappeared, and again dissipated after discontinuation of the ginkgo product. The relationship between ginkgo and mood dysregulation was considered to be "probable" based on the Naranjo adverse drug reaction probability scale (96763); however, the exact mechanism by which ginkgo may have affected mood regulation is unknown.
General
...Orally and topically, gotu kola seems to be well tolerated.
Most Common Adverse Effects:
Orally: Gastric irritation and nausea.
Topically: Eczema.
Serious Adverse Effects (Rare):
Orally: Hepatotoxicity.
Dermatologic ...Topically, gotu kola may cause eczema (10277,10278). Also, gotu kola can cause allergic contact dermatitis, characterized by erythema, itching, papules, and a burning sensation (4,6887,9789,52875,52887,52896,52902). One specific gotu kola product (Blasteostimulina,Almirall, S. A.) has been reported to cause allergic contact dermatitis. However, not all patients with reactions to this product are sensitive to gotu kola; some patients are sensitive to neomycin, another ingredient in the product (52875). Madecassol ointment (Rona Laboratories Limited) is another gotu kola product that has resulted in allergic contact dermatitis. Controlled testing suggests that this product can cause this adverse effect in about 8% of patients (9789). Centellase cream has also caused allergic contact dermatitis in at least two cases (52887,52888).
Gastrointestinal ...In some patients, gotu kola can extract cause gastrointestinal upset and nausea (780,6887,52894).
Hepatic
...There is concern that gotu kola may cause liver toxicity in some patients.
There are at least four case reports of hepatotoxicity associated with gotu kola; however, hepatotoxic contaminants cannot be ruled out, as laboratory analysis was not conducted on the products used. Additionally, the doses of gotu kola used in these cases were not reported (13182,92506). In a clinical trial where liver function was monitored, taking gotu kola 120 mg daily for 6 months was not associated with changes in liver function (11065).
In one case of hepatotoxicity, a 61-year-old female developed elevated liver transaminase and total bilirubin levels after taking gotu kola tablets for 30 days. Liver biopsy showed granulomatous acute hepatitis. Months later, the patient took gotu kola again and developed elevated liver transaminases after 2 weeks. In another case, a 52-year-old female developed symptoms of hepatitis and increased liver transaminases after taking gotu kola for 3 weeks. Biopsy indicated chronic hepatitis and granulomas, areas of necrosis, and cirrhotic transformation. Liver function normalized after discontinuation of gotu kola. In a third case, a 49-year-old female developed symptoms of hepatitis after taking gotu kola for 2 months. Biopsy revealed granulomatous hepatitis. Liver function normalized after discontinuation of gotu kola (13182). In a fourth case, a 15-year-old female taking an unknown dose of gotu kola and lymecycline for 6 weeks for acne experienced acute liver failure with abdominal pain and vomiting, as well as elevated liver transaminases, bilirubin, international normalized ratio (INR), and prothrombin. Liver function returned to normal after both products were discontinued (92506).
Immunologic ...Topically, gotu kola can cause allergic contact dermatitis, characterized by erythema, itching, papules, and a burning sensation (4,6887,9789,52875,52887,52896,52902). One specific gotu kola product (Blasteostimulina, Almirall, S. A.) has been reported to cause allergic contact dermatitis in some patients. However, not all patients who react to this product are sensitive to gotu kola; some are sensitive to neomycin, another ingredient in the product (52875). Madecassol ointment (Rona Laboratories Limited) is another gotu kola product that has resulted in allergic contact dermatitis. Controlled testing suggests that this product can cause this adverse effect in about 8% of patients (9789). Centellase cream has also caused allergic contact dermatitis in at least two cases (52887,52888).
Psychiatric ...A case of night eating syndrome has been reported for a 41-year-old female who had been taking a gotu kola tincture (dose not specified) for 2 years. Symptoms resolved after gotu kola use was discontinued (52878).
General
...Orally, valerian is generally well-tolerated.
Most Common Adverse Effects:
Orally: Dizziness, drowsiness, and mental slowness. Other reported side effects include headache, gastrointestinal upset, excitability, and vivid dreams. When used chronically and abruptly stopped, symptoms of withdrawal such as tachycardia, anxiety, irritability, and insomnia might occur. Advise patients to taper doses slowly after extended use.
Serious Adverse Effects (Rare):
Orally: Several case reports raise concerns about hepatotoxicity after the use of valerian and valerian-containing multi-ingredient dietary supplements. Withdrawal from chronic valerian use has been associated with cases of cardiac failure and hallucinations.
Cardiovascular ...When used orally in high doses for an extended period of time, valerian withdrawal has been associated with tachycardia and high output cardiac failure in one patient with a history of coronary artery disease (3487). Chest tightness has been reported for an 18-year-old female who took 40-50 capsules containing valerian 470 mg/capsule (659). A case of severe hypotension, suspected to be due to vasodilation, hypocalcemia, and hypokalemia, has been reported for a patient who injected an unknown quantity of a crude tap water extract of raw valerian root (81734).
Dermatologic ...Orally, valerian might rarely cause a rash. A case of valerian-related rash that resolved after valerian root discontinuation was reported in clinical research (19422).
Gastrointestinal ...Orally, valerian has been associated with increased incidence of gastrointestinal problems including diarrhea, nausea, vomiting, and stomach pain (15046,19406,19407,19422,110712). In one individual, taking 20 times the normal dose caused abdominal cramping (659).
Hepatic
...There have been several case reports of hepatotoxicity associated with the use of multi-ingredient oral preparations containing valerian (8243,96241).
In one case report, a 57-year-old man presented with acute hepatitis after consuming a cold and flu remedy containing valerian 2 grams for 3 days; the remedy also contained white willow, elderberry, and horseradish. Although the use of the cold and flu remedy was discontinued one month prior to symptom presentation, the acute hepatitis was attributed to valerian root and treated with steroids (96241). It is possible, however, that some of these preparations may have been adulterated with hepatotoxic agents (8243).
Hepatotoxicity involving long-term use of single-ingredient valerian preparations has also been reported (3484,17578). Also, a case of a 38-year-old female with liver insufficiency and cirrhosis of a vascular parenchymal nature who developed hepatotoxic symptoms following valerian and ethyl-alcohol abuse has been reported (81697). Symptoms resolved and laboratory values normalized following intense plasmapheresis treatment. Another case of acute hepatitis characterized by elevated aminotransferases, mild fibrosis, and liver inflammation has been reported for a 50-year-old female who consumed valerian root extract 5 mL three times weekly along with 10 tablets of viamine, a product containing dry valerian extract 125 mg/tablet, for 2 months (81696). Because a variety of doses were used in these cases, and many people have used higher doses safely, these hepatotoxic reactions might have been idiosyncratic. Tell patients the long-term effect of valerian on liver function is unknown.
Musculoskeletal ...In a case report, combined intake of valerian and passionflower caused throbbing and muscular fatigue when taken concomitantly with lorazepam (19429).
Neurologic/CNS ...Orally, valerian might cause dizziness, headaches, fatigue, sleepiness, and mental dullness (3484,17578,19411,19422,81723,89407). The severity of adverse effects appears to increase with higher doses (19411). However, taking valerian extracts in doses up to 1800 mg does not appear to significantly affect mood or psychomotor performance (10424,15044). Valerian does not usually have a negative impact on reaction time, alertness, and concentration the morning after intake (2074,8296). Clinical research shows that a single dose of valerian root 1600 mg is not associated with any changes in sleepiness, reaction time, or driving performance within 1-4 hours after intake (96240). More serious side effects may occur when valerian is taken at higher doses. In one individual, 20 times the normal dose caused tremor of the hand and foot and lightheadedness (659). In a case report, combined intake of valerian and passionflower caused shaking of the hands and dizziness when taken concomitantly with lorazepam (19429).
Psychiatric ...Orally, valerian has been associate with reports of restlessness, excitability, uneasiness, agitation, and vivid dreams (3484,17578,19411,19422). Chronic use and rapid cessation can lead to withdrawal syndrome with symptoms of agitation, insomnia, and hallucinations (104003). There appears to be a trend towards increased severity of adverse effects with higher doses (19411). A case of acute hypomania has been reported for a 21-year-old female patient who took a valerian decoction in water each night for one month to treat subclinical anxiety. Symptoms included euphoric mood, rapid speech, and increased sociability and sexual interest. Following cessation of valerian use and treatment with quetiapine 100 mg daily for two weeks, the patient recovered (89405). In another case report, an 85-year-old male with mild cognitive impairment, major depression, anxiety, and chronic kidney disease presented to the emergency department with hallucinations, confusion, and agitation thought to be due to abrupt cessation after taking valerian 600 mg daily for about 6 months. The symptoms resolved in about 5 days (104003).
