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Dietary supplement

Synaptin Ingredients & Drug Interactions

by Ecological Formulas

Capsule Category: Other Combinations
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

Synaptin is a dietary supplement by Ecological Formulas with 5 active ingredients. Its ingredients are commonly taken for memory and cognitive support, brain blood flow, stroke recovery.Based on those ingredients, 1,375 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ginkgo biloba Leaf Extract, Bacopa monnieri Extract, Huperzine A. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Synaptin by Ecological Formulas

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 5 of its 5 active ingredients.
  • “Thiamine Tetrahydrofurfuryl Disulfide” is listed as a grouped ingredient — the label gives one combined amount (15 mg) without saying how much of each component you get.

Synaptin contains five active ingredients. Thiamine (vitamin B1) is essential for nerve function and energy metabolism.

Vinpocetine is thought to improve blood flow to the brain. Bacopa monnieri extract is a traditional herb used in Ayurvedic medicine, believed to support cognitive function.

Huperzine A is a compound derived from club moss that acts as an acetylcholinesterase inhibitor — it slows the breakdown of acetylcholine, a neurotransmitter involved in memory and learning. Ginkgo biloba leaf extract comes from an ancient tree and is used to support circulation and cognitive health.

The product also contains inactive ingredients — cellulose, gelatin, magnesium stearate, and silicon dioxide — which serve as fillers, binders, and capsule material.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: cognitive improvement and memory support.
  • We looked for evidence on: Age-related cognitive decline, Alzheimer disease, Anxiety, Attention deficit-hyperactivity disorder (ADHD), Cognitive function, Cognitive impairment — and 4 related terms.
  • The strongest evidence on file: Vinpocetine is rated "Possibly Effective" for Dementia (Natural Medicines).
  • Also on file: Ginkgo is rated "Possibly Effective" for Anxiety, Dementia.
  • Also on file: Huperzine A is rated "Possibly Effective" for Alzheimer disease.

The evidence for Synaptin's ingredients is mixed. Thiamine is effective for thiamine deficiency and Wernicke-Korsakoff syndrome (a serious brain condition from vitamin B1 deficiency).

For ginkgo biloba, there is possibly effective evidence for hearing loss, stroke recovery, schizophrenia, premenstrual syndrome, dementia, and anxiety. Huperzine A is possibly effective for Alzheimer disease.

However, for most of bacopa's proposed uses — including Alzheimer disease, cognitive function, ADHD, and back pain — the evidence is insufficient to rate. Similarly, vinpocetine shows possibly effective evidence only for dementia; tinnitus, motion sickness, stroke, and chronic fatigue syndrome lack sufficient evidence to rate.

Because most of the ingredients in this product are promoted for cognition and brain health but lack strong evidence, talk with your doctor or pharmacist about whether this product is right for your particular situation.

The evidence, ingredient by ingredient Vinpocetine Bacopa Thiamine Ginkgo Huperzine A

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Thiamine is generally very safe when taken by mouth in normal amounts and is likely safe in pregnancy and while breastfeeding — in fact, thiamine is needed during these times, though use supplement doses only as your doctor advises. Vinpocetine is generally well tolerated short-term but long-term safety isn't well established; the FDA has advised that people who are pregnant or could become pregnant should not use it, and it should be avoided while breastfeeding.

Bacopa is generally well tolerated in studies, though gastrointestinal side effects (abdominal cramps, diarrhea, nausea, bloating) occur in 12% to 30% of users; it should be avoided in pregnancy and while breastfeeding due to insufficient safety data. Ginkgo is generally well tolerated in healthy adults but may increase bleeding risk — it should be avoided in pregnancy and while breastfeeding.

Huperzine A is a pharmacologically active compound that can cause real side effects (cholinergic effects like blurred vision, diarrhea, nausea, decreased heart rate) and should be avoided in pregnancy and while breastfeeding. Common side effects across the ingredients include dizziness, headache, gastrointestinal upset, and sleep disturbances.

Side effects, ingredient by ingredient Vinpocetine Bacopa Thiamine Ginkgo Huperzine A

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 5 of the 5 matched ingredients can interact with medications — Vinpocetine, Ginkgo, Bacopa, Huperzine A, Thiamine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 1,376 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking Synaptin, check with your doctor or pharmacist if you're on any of the following: beta-blockers like talinolol (Major severity), blood thinners or antiplatelet drugs, medications metabolized by your liver (including certain cholesterol, heart, diabetes, psychiatric, and immunosuppressant drugs), anticholinergic or cholinergic medications, and trimethoprim (an antibiotic). If you take any of these, the checker below will help you see which ingredients and drugs are flagged.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

Synaptin is a cognitive-support formula with some evidence behind individual ingredients (especially thiamine and ginkgo for specific conditions), but most proposed benefits lack strong scientific backing. If you take blood thinners, heart medications, diabetes drugs, antidepressants, or immunosuppressants, this product is not something to add without checking with your doctor or pharmacist first — the interaction risks are real.

Pregnant people and those breastfeeding should avoid it entirely. Talk with your own healthcare provider about whether this product fits your health goals and won't interfere with your medications.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 5 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 14, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Synaptin, straight from the product label.

Brand Ecological Formulas
Barcode (UPC) 696859131929
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Dec 14, 2023
DSLD ID 299789
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Synaptin by Ecological Formulas, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
60
UPC/BARCODE
696859131929
IngredientAmount% DV
Thiamine11 mg733%
Vinpocetine2.5 mg--
Bacopa monnieri Extract60 mg--
Thiamine Tetrahydrofurfuryl Disulfide15 mg--
Ginkgo biloba Leaf Extract50 mg--
Huperzine A50 mcg--

Other ingredients: Cellulose, Gelatin, Magnesium Stearate, Silicon Dioxide

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Statement of Identity

Dietary Supplement

Formula

Synaptin is a scientifically designed dietary supplement containing a unique blend of naturally occurring neuromodulating agents.

Formulation

This product contains a comprehensive blend of standardized herbal extracts which serve as nutritional adjuncts to cognitive improvement.

Neuro Axonal Formula

Suggested/Recommended/Usage/Directions

Directions Take one capsule daily between meals or as directed by a physician.

Precautions

Not intended for use by children or during pregnancy.

Not intended for use by children or during pregnancy.

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

See for yourself

Synaptin by Ecological Formulas label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in Synaptin by Ecological Formulas

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Vinpocetine

Interacts with
208 drugs
2.5 mg per serving

Vinpocetine is a lab-made compound based on a chemical from the periwinkle plant, and it is marketed mainly for memory and brain health. The evidence...

Vinpocetine monograph & interactions

Bacopa monnieri Extract

Interacts with
930 drugs
60 mg per serving Form: Bacosides

Bacopa is an Ayurvedic herb most often used for memory and thinking. Some small studies suggest it may modestly help memory when taken regularly for s...

Bacopa monnieri Extract monograph & interactions
15 mg per serving

Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get eno...

Thiamine Tetrahydrofurfuryl Disulfide monograph & interactions

Ginkgo biloba Leaf Extract

Interacts with
1,266 drugs
50 mg per serving Form: Ginkgosides

Ginkgo is one of the world's most popular herbal supplements, mostly taken to support memory and circulation. The evidence for these uses is mixed and...

Ginkgo biloba Leaf Extract monograph & interactions

Huperzine A

Interacts with
219 drugs
50 mcg per serving Form: Huperzia serrata

Huperzine A is a purified compound from a Chinese clubmoss that acts like a mild cholinesterase inhibitor, similar in mechanism to some prescription A...

Huperzine A monograph & interactions

Other (inactive) ingredients: Cellulose, Gelatin, Magnesium Stearate, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Synaptin by Ecological Formulas Drug Interactions

Want to check YOUR meds against Synaptin?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
1,375Drugs
1 Major 1,359 Moderate 15 Minor

Each ingredient & the kinds of drugs it affects

For each ingredient in Synaptin with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Ginkgo biloba Leaf Extract23 drug types · 1,266 drugs

Talinolol

Taking ginkgo with talinolol seems to increase blood levels of talinolol.
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.

Likelihood Probable Evidence B
Alprazolam (Xanax)

Theoretically, ginkgo might decrease the levels and clinical effects of alprazolam.
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.

Likelihood Probable Evidence B
Anticoagulant/Antiplatelet Drugs

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.
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. Several case reports have documented serious bleeding events in patients taking ginkgo. 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. 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. 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. It has been suggested that ginkgo has to be taken for at least 2-3 weeks to have a significant effect on platelet aggregation. 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. In addition, a single dose of ginkgo plus clopidogrel or ticlopidine does not seem to significantly increase bleeding time or platelet aggregation. 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.

Likelihood Possible Evidence A
Anticonvulsants

Theoretically, ginkgo might reduce the effectiveness of anticonvulsants.
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. Ginkgo leaf extract contains trace amounts of ginkgotoxin. The amount of ginkgotoxin in ginkgo leaf and leaf extract seems unlikely to cause toxicity. 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.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, taking ginkgo with antidiabetes drugs might alter the response to antidiabetes drugs.
Ginkgo leaf extract seems to alter insulin secretion and metabolism, and might affect blood glucose levels in people with type 2 diabetes. 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.

Likelihood Possible Evidence B
Atorvastatin (Lipitor)

Theoretically, ginkgo might decrease the levels and clinical effects of atorvastatin.
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. 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.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, ginkgo might increase levels of drugs metabolized by CYP1A2.
Laboratory research suggests that ginkgo leaf extract can mildly inhibit CYP1A2 enzymes. However, clinical research suggests ginkgo might not affect CYP1A2. Until more is known, use ginkgo cautiously in patients taking drugs metabolized by these enzymes.

Likelihood Possible Evidence B
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, ginkgo might decrease levels of drugs metabolized by CYP2C19.
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. 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.

Likelihood Probable Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, ginkgo might increase levels of drugs metabolized by CYP2C9.
In vitro, a specific standardized extract of ginkgo leaf (EGb 761) inhibits CYP2C9 activity . 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.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, ginkgo might decrease levels of drugs metabolized by CYP3A4.
There is conflicting evidence about whether ginkgo induces or inhibits CYP3A4. Ginkgo does not appear to affect hepatic CYP3A4. 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. Other clinical research also suggests ginkgo does not significantly affect CYP3A4 activity. 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).

Likelihood Possible Evidence B
Efavirenz (Sustiva)

Theoretically, ginkgo might decrease the levels and clinical effects of efavirenz.
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). 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.

Likelihood Possible Evidence D
Ibuprofen (Advil, Others)

Theoretically, ginkgo might increase the risk of bleeding when used with ibuprofen.
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. 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.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, taking ginkgo with P-glycoprotein substrates might increase the levels and adverse effects of these substrates.
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.

Likelihood Possible Evidence B
Risperidone (Risperdal)

Theoretically, taking ginkgo with risperidone might increase the levels and adverse effects of risperidone.
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. 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.

Likelihood Possible Evidence D
Rosiglitazone (Avandia)

Theoretically, ginkgo might decrease the levels and clinical effects of rosiglitazone.
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.

Likelihood Possible Evidence D
Seizure Threshold Lowering Drugs

Theoretically, taking ginkgo with drugs that lower the seizure threshold might increase the risk for convulsions.
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. Ginkgo leaf extract contains trace amounts of ginkgotoxin. The amount of ginkgotoxin in ginkgo leaf and leaf extract seems unlikely to cause toxicity. 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.

Likelihood Possible Evidence D
Simvastatin (Zocor)

Theoretically, ginkgo might decrease the levels and clinical effects of simvastatin.
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.

Likelihood Probable Evidence B
Sofosbuvir (Sovaldi)

Theoretically, ginkgo might increase the levels and clinical effects of sofosbuvir.
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.

Likelihood Possible Evidence D
Tacrolimus (Prograf)

Theoretically, ginkgo might increase the blood levels of tacrolimus.
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.

Likelihood Possible Evidence D
Trazodone (Desyrel)

Theoretically, ginkgo might increase the levels and clinical effects of trazodone.
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.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Ginkgo has been shown to increase the risk of bleeding in some people when taken with warfarin.
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. Several case reports have documented serious bleeding events in patients taking ginkgo. Information from a medical database suggests that when taken concurrently with warfarin, ginkgo increases the risk of a bleeding adverse event by 38%. 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. 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. 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. 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.

Likelihood Possible Evidence B
Nifedipine (Procardia)

Theoretically, taking ginkgo with oral, but not intravenous, nifedipine might increase levels and adverse effects of nifedipine.
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. However, taking ginkgo orally does not seem to affect the pharmacokinetics of intravenous nifedipine.

Likelihood Possible Evidence B
Omeprazole (Prilosec)

Theoretically, taking ginkgo with omeprazole might decrease the levels and clinical effects of omeprazole.
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%.

Likelihood Possible Evidence B

Bacopa monnieri Extract8 drug types · 930 drugs

Anticholinergic Drugs

Theoretically, concurrent use might decrease the effectiveness of both agents.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels, which could counteract the effects of anticholinergic drugs. Similarly, anticholinergic drugs might counteract the cholinergic effects of bacopa.

Likelihood Possible Evidence D
Cevimeline (Evoxac)

Theoretically, bacopa might increase the effects and adverse effects of cevimeline.
In one case, a 58-year-old female taking cevimeline long-term for Sjogren syndrome experienced hyperhidrosis, malaise, nausea, and tachycardia shortly after taking a single dose of bacopa. Symptoms resolved after two days. Cevimeline is metabolized by cytochrome P450 (CYP) 2D6 and CYP3A4, and researchers theorize that bacopa may have inhibited these isoenzymes. However, it is unclear if bacopa causes clinically significant inhibition of either CYP2D6 or CYP3A4.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of bacopa with other cholinergic drugs might have additive effects.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels. Theoretically, this could result in additive cholinergic effects when used with cholinergic drugs.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP1A2 substrates.
Research on the effects of bacopa extracts on CYP1A2 enzymes is conflicting. Some in vitro evidence shows that bacopa extract can moderately and non-competitively inhibit CYP1A2, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP2C19 substrates.
In vitro evidence suggests that bacopa extract can moderately and non-competitively inhibit CYP2C19 enzymes. It is not known whether this is clinically significant.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP2C9 substrates.
Research on the effect of bacopa extracts on CYP2C9 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and non-competitively inhibit CYP2C9, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP3A4 substrates.
Research on the effects of bacopa extracts on CYP3A4 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and competitively inhibit CYP3A4, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, bacopa might have additive effects when used with thyroid hormone.
Animal research suggests that bacopa increases thyroxine (T4) levels in mice by about 40%.

Likelihood Possible Evidence D

Huperzine A2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, huperzine A might decrease the effects of anticholinergic drugs.
Huperzine A has acetylcholinesterase (AChE) inhibiting effects. In animal models, huperzine A reversed cognitive deficits induced by scopolamine, an anticholinergic drug.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of huperzine A with cholinergic drugs might increase the effects and side effects of these medications.
Huperzine A can inhibit acetylcholinesterase (AChE) and might cause cumulative effects if used with cholinergic drugs.

Likelihood Possible Evidence B

Vinpocetine3 drug types · 208 drugs

Anticoagulant/Antiplatelet Drugs

Vinpocetine might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Clinical research shows that vinpocetine decreases red blood cell aggregation, as well as plasma and whole blood viscosity. This effect has been seen with intravenous vinpocetine 1 mg/kg and oral vinpocetine 30 mg daily. Vinpocetine also seems to have antiplatelet effects.

Likelihood Possible Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, vinpocetine might increase levels of drugs metabolized by CYP2C9.
In vitro research shows that vinpocetine weakly inhibits CYP2C9. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Vinpocetine might modestly increase the risk of bleeding when taken with warfarin.
Clinical research shows that the combination of warfarin and vinpocetine leads to slight increases in prothrombin time and the area under the concentration curve for warfarin. However, these increases were small, and researchers suggest that this interaction is not likely to be clinically significant in most patients.

Likelihood Possible Evidence B

Thiamine Tetrahydrofurfuryl Disulfide1 drug type · 3 drugs

Trimethoprim (Proloprim)

Trimethoprim might increase blood levels of thiamine.
In vitro, animal, and clinical research suggest that trimethoprim inhibits intestinal thiamine transporter ThTR-2, hepatic transporter OCT1, and renal transporters OCT2, MATE1, and MATE2, resulting in paradoxically increased thiamine plasma concentrations.

Likelihood Probable Evidence B
The maker

Brand information

Manufacturer and brand details for Synaptin, from the product label.

Ecological Formulas

See all Ecological Formulas products
Name
Ecological Formulas
Street Address
1061-B Shary Circle
City
Concord
State
CA
ZipCode
94518
Pharmacist Counseling Corner

Synaptin by Ecological Formulas: Common Questions

Does Synaptin by Ecological Formulas interact with any medications?
Yes. Based on its ingredients, Synaptin has a known interaction with 1,375 medications, including 1 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Synaptin contains 5 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take Synaptin if I'm on a blood thinner like warfarin?
No — both vinpocetine and ginkgo in this product can increase your bleeding risk when combined with blood thinners or antiplatelet drugs. Talk with your doctor or pharmacist before starting; you may need to skip this product or adjust your blood thinner dose.
Is Synaptin safe during pregnancy?
No. Vinpocetine, bacopa, ginkgo, and huperzine A should all be avoided during pregnancy due to insufficient safety data or possible risk. Thiamine is needed in pregnancy, but only at supplement doses your doctor recommends — you shouldn't use a multi-ingredient product like this without medical guidance.
What does huperzine A do?
Huperzine A slows the breakdown of acetylcholine, a brain chemical involved in memory and learning. It's possibly effective for Alzheimer disease, though evidence is limited. It can cause cholinergic side effects like nausea, diarrhea, blurred vision, and decreased heart rate.
How often do people get side effects from these ingredients?
Bacopa causes gastrointestinal side effects in 12% to 30% of users. Common side effects across the ingredients include dizziness, headache, nausea, and sleep problems. Serious side effects are rare but reported, especially with ginkgo (cardiac arrhythmias and bleeding).
Does this product really help with memory and brain fog?
Thiamine works for B1 deficiency, and ginkgo has possibly effective evidence for dementia. But bacopa, vinpocetine, and huperzine A show insufficient or weak evidence for cognitive function in otherwise healthy people. Results vary, and the science isn't strong enough to guarantee benefit.
What are the inactive ingredients?
The inactive ingredients are cellulose, gelatin, magnesium stearate, and silicon dioxide — fillers, a binder, and capsule material. There are no unusual or hard-to-pronounce additives.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Synaptin label
Go deeper

The Full Monographs Behind Synaptin’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Sources

Sources & How We Checked

Synaptin's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 156 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Thiamine 7 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  4. Rogovik, A. L., Vohra, S., and Goldman, R. D. Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? Ann.Pharmacother. 2010;44(2):311-324. PubMed
  5. Arruti N, Bernedo N, Audicana MT, Villarreal O, Uriel O, Muñoz D. Systemic allergic dermatitis caused by thiamine after iontophoresis. Contact Dermatitis. 2013 Dec;69(6):375-6. PubMed
  6. Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
  7. Vora B, Wen A, Yee SW, et al. The Effect of Trimethoprim on Thiamine Absorption: A Transporter-Mediated Drug-Nutrient Interaction. Clin Pharmacol Ther 2023;114(2):381-392.

See these in context on the Thiamine monograph →

Vinpocetine 27 references
  1. Hindmarch I, Fuchs HH, Erzigkeit H. Efficacy and tolerance of vinpocetine in ambulant patients suffering from mild to moderate organic psychosyndromes. Int Clin Psychopharmacol 1991;6:31-43. PubMed
  2. Balestreri R, Fontana L, Astengo F. A double-blind placebo controlled evaluation of the safety and efficacy of vinpocetine in the treatment of patients with chronic vascular senile cerebral dysfunction. J Am Geriatr Soc 1987;35:425-30. PubMed
  3. Akopov SE, Gabrielian ES. Effects of aspirin, dipyridamole, nifedipine and cavinton which act on platelet aggregation induced by different aggregating agents alone and in combination. Eur J Clin Pharmacol 1992;42:257-9. PubMed
  4. Kidd PM. A review of nutrients and botanicals in the integrative management of cognitive dysfunction. Altern Med Rev 1999;4:144-61..
  5. Wollschlaeger B. Efficacy of vinpocetine in the management of cognitive impairment and memory loss. JANA 2001;4:25-30.
  6. Hitzenberger G, Sommer W, Grandt R. Influence of vinpocetine on warfarin-induced inhibition of coagulation. Int J Clin Pharmacol Ther Toxicol 1990;28:323-8..
  7. Dekoninck, W. J., Jocquet, P., Jacquy, J., and Henriet, M. Comparative study of the clinical effects of vincamine + glycerol versus glycerol + placebo in the acute phase of stroke. Arzneimittelforschung. 1978;28(9):1654-1657.
  8. Fischhof, P. K., Moslinger-Gehmayr, R., Herrmann, W. M., Friedmann, A., and Russmann, D. L. Therapeutic efficacy of vincamine in dementia. Neuropsychobiology 1996;34(1):29-35. PubMed
  9. Feher, G., Koltai, K., Kesmarky, G., Horvath, B., Toth, K., Komoly, S., and Szapary, L. Effect of parenteral or oral vinpocetine on the hemorheological parameters of patients with chronic cerebrovascular diseases. Phytomedicine. 2009;16(2-3):111-117. PubMed
  10. Kuzuya, F. Effects of vinpocetine on platelet aggregability and erythrocyte deformability. Ther Hung. 1985;33(1):22-34.
  11. Kovacs, L. Cavinton in the treatment of acute stroke. Ther Hung. 1985;33(1):50-57.
  12. Osawa, M. and Maruyama, S. Effects of TCV-3B (vinpocetine) on blood viscosity in ischemic cerebrovascular diseases. Ther.Hung. 1985;33(1):7-12.
  13. Ebi, O. Open-labeled phase III clinical trials with vinpocetine in Japan. Ther.Hung. 1985;33(1):41-49.
  14. Richichi, I., Valsecchi, O., Falcone, C., Sofi, A., and Zanini, L. [A case of "torsade de pointe" during vincamine therapy]. Minerva Cardioangiol. 1978;26(3):197-200.
  15. Dany, F., Merle, L., Goudoud, J. C., Liozon, F., Blanc, P., Bouvot, J. C., Nicot, G., and Dangoumau, J. [Cardiac toxicity of vincamine: a seven cases report of ventricular arrhythmias by parenteral administration of vincamine (author's transl)]. Therapie
  16. Fenzl, E., Apecechea, M., Schaltenbr, R., and Fridel, R. Long term study concerning tolerance and efficacy of vinpocetine in elderly patients suffering from a mild to moderate organic psychosyndrome. Senile dementia: early detection 1986;580-585.
  17. Peruzza, M. and DeJacobis, M. A double-blind placebo controlled evaluation of the efficacy and safety of vinpocetine in the treatment of patients with chronic vascular or degenerative senile cerebral dysfunction. ADV THER 1986;3(4):201-209.
  18. Manconi, E., Binaghi, F., and Pitzus, F. A double-blind clinical trial of vinpocetine in the treatment of cerebral insufficiency of vascular and degenerative origin. CURR THER RES, CLIN EXP 1986;40(4):702-709.
  19. Blaha, L., Erzigkeit, H. L., Adamczyk, L. A., Freytag, L. S., and Schaltenbrand, R. Clinical evidence of the effectiveness of vinpocetine in the treatment of organic psychosyndrome. Human Psychopharmacology: Clinical & Experimental 1989;4(2):103-111. DOI
  20. Shimizu, Y., Saitoh, K., Nakayama, M., Suto, K., Daikohara, R., and Nemoto, T. Agranulocytosis induced by vinpocetine. Medicine On-line 2011;
  21. Kong L, Song C, Ye L, et al. The Effect of Vinpocetine on Human Cytochrome P450 Isoenzymes by Using a Cocktail Method. Evid Based Complement Alternat Med. 2016;2016:5017135. PubMed
  22. Vinpocetine in Dietary Supplements. FDA Food/Dietary Supplements/Products & Ingredients. Available at: http://www.fda.gov/Food/DietarySupplements/ProductsIngredients/ucm518478.htm. Accessed 6 September 2016.
  23. Statement on warning for women of childbearing age about possible safety risks of dietary supplements containing vinpocetine. FDA Food/Dietary Supplements/Products & Ingredients. Available at: https://www.fda.gov/news-events/press-announcements/statement-
  24. Zhang W, Huang Y, Li Y, et al. Efficacy and safety of vinpocetine as part of treatment for acute cerebral infarction: A randomized, open-label, controlled, multicenter CAVIN (Chinese Assessment for Vinpocetine in Neurology) trial. Clin Drug Investig 2016; PubMed
  25. National Toxicology Program. NTP technical report on the prenatal development toxicity studies of vinpocetine (CAS No. 42971-09-5) in Sprague Dawley Rats and New Zealand White Rabbits (Gavage Studies). Research Triangle Park, NC: National Toxicology Progr
  26. Gutiérrez-Farfán I, Reyes-Legorreta C, Solís-Olguín M, Alatorre-Miguel E, Verduzco-Mendoza A, Durand-Rivera A. Evaluation of vinpocetine as a therapy in patients with sensorineural hearing loss: a phase II, open-label, single-center study. J Pharmacol Sci PubMed
  27. Hu X, Guo K, Li J, et al. Postoperative ecchymoma of eyelid after botulinum toxin injection for hemifacial spasm: a case report. Front Neurol 2023;14:1171303. PubMed

See these in context on the Vinpocetine monograph →

Bacopa 12 references
  1. Stough C, Lloyd J, Clarke J, et al. The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology 2001;156:481-4..
  2. Yadav SK, Jain AK, Tripathi SN, Gupta JP. Irritable bowel syndrome: therapeutic evaluation of indigenous drugs. Indian J Med Res 1989;90:496-503..
  3. Morgan A, Stevens J. Does Bacopa monnieri improve memory performance in older persons? Results of a randomized, placebo-controlled, double-blind trial. J Altern Complement Med 2010;16:753-9.
  4. Kar, A., Panda, S., and Bharti, S. Relative efficacy of three medicinal plant extracts in the alteration of thyroid hormone concentrations in male mice. J Ethnopharmacol. 2002;81(2):281-285. PubMed
  5. Mukherjee, G. D. and Dey, C. D. Clinical trial on Brahmi. I. J.Exp.Med.Sci. 1966;10(1):5-11.
  6. Kar A, Pandit S, Mukherjee K, Bahadur S, Mukherjee PK. Safety assessment of selected medicinal food plants used in Ayurveda through CYP450 enzyme inhibition study. J Sci Food Agric 2017;97(1):333-40. doi: 10.1002/jsfa.7739. PubMed
  7. Kongkeaw C, Dilokthornsakul P, Thanarangsarit P, et al. Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract. J Ethnopharmacol 2014;151(1):528-35. PubMed
  8. Ramasamy S, Kiew LV, Chung LY. Inhibition of human cytochrome P450 enzymes by Bacopa monnieri standardized extract and constituents. Molecules 2014;19(2):2588-601. PubMed
  9. Prabhakar S, Vishnu VY, Modi M, et al. Efficacy of Bacopa monnieri (Brahmi) and donepezil in Alzheimer's disease and mild cognitive impairment: a randomized double-blind parallel phase 2b study. Ann Indian Acad Neurol 2020;23(6):767-73. PubMed
  10. Acquarulo B, Tandon P, Macica CM. Suspected cholinergic toxicity due to cevimeline hydrochloride and Bacopa monnieri interaction: a case report. J Med Case Rep 2022;16(1):253. PubMed
  11. Keegan AP, Stough C, Paris D, et al. Bacopa monnieri supplementation has no effect on serum brain-derived neurotrophic factor levels but beneficially modulates nuclear factor kappa B and cyclic AMP response element-binding protein levels in healthy elderl
  12. Yaworski AM, Blyumin M, Chang T, Mammen AL, Greene M. Necrotizing myopathy with elevated anti-HMGCR antibodies following exposure to the supplement Bacopa. Muscle Nerve 2023;67(2):E1-E3.

See these in context on the Bacopa monograph →

Ginkgo 97 references
  1. Davydov L, Stirling AL. Stevens-Johnson syndrome with Ginkgo biloba. J Herb Pharmacother 2001;1:65-9. DOI
  2. Benjamin J, Muir T, Briggs K, Pentland B. A case of cerebral haemorrhage-can Ginkgo biloba be implicated? Postgrad Med J 2001;77:112-3.
  3. Matthews, MK. Association of Ginkgo biloba with intracerebral hemorrhage. Neurology 1998;50:1934.
  4. Rowin J, Lewis SL. Spontaneous bilateral subdural hemotomas with chronic Ginkgo biloba ingestion. Neurology 1996;46:1775-6.
  5. Rosenblatt M, Mindel T. Spontaneous hyphema associated with ingestion of Ginkgo biloba extract. N Engl J Med 1997;336:1108.
  6. Fessenden JM, Wittenborn W, Clarke L. Gingko biloba: a case report of herbal medicine and bleeding postoperatively from a laparoscopic cholecystectomy. Am Surg 2001;67:33-5. DOI
  7. Gurley BJ, Gardner SF, Hubbard MA. Clinical assessment of potential cytochrome P450-mediated herb-drug interactions. AAPS Ann Mtg & Expo Indianapolis, IN: 2000; Oct 29 - Nov 2:presentation #3460.
  8. Cohen AJ, Bartlik B. Ginkgo biloba for antidepressant-induced sexual dysfunction. J Sex Marital Ther 1998;24:139-43. PubMed
  9. Kudolo GB. The effect of 3-month ingestion of Ginkgo biloba extract on pancreatic beta-cell function in response to glucose loading in normal glucose tolerant individuals. J Clin Pharmacol 2000;40:647-54.
  10. Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7. DOI
  11. Cesarani A, Meloni F, Alpini D, et al. Ginkgo biloba (EGb 761) in the treatment of equilibrium disorders. Adv Ther 1998;15:291-304.
  12. Galluzzi S, Zanetti O, Binetti G, et al. Coma in a patient with Alzheimer's disease taking low dose trazodone and Ginkgo biloba. J Neurol Neurosurg Psychiatry 2000;68:679-80. DOI
  13. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  14. Gregory PJ. Seizure associated with Ginkgo biloba? Ann Intern Med 2001;134:344.
  15. Granger AS. Ginkgo biloba precipitating epileptic seizures. Age Ageing 2001;30:523-5. PubMed
  16. Kajiyama Y, Fujii K, Takeuchi H, Manabe Y. Ginkgo seed poisoning. Pediatrics 2002;109:325-7. PubMed
  17. Miwa H, Iijima M, Tanaka S, Mizuno Y. Generalized convulsions after consuming a large amount of gingko nuts. Epilepsia 2001;42:280-1. DOI
  18. Burschka MA, Hassan HA, Reineke T, et al. Effect of treatment with Ginkgo biloba extract EGb 761 (oral) on unilateral idiopathic sudden hearing loss in a prospective randomized double-blind study of 106 outpatients. Eur Arch Otorhinolaryngol 2001;258:213- PubMed
  19. Miller LG, Freeman B. Possible subdural hematoma associated with Ginkgo biloba. J Herb Pharmacother 2002;2:57-63.
  20. Kudolo GB, Dorsey S, Blodgett J. Effect of the ingestion of Ginkgo biloba extract on platelet aggregation and urinary prostanoid excretion in healthy and Type 2 diabetic subjects. Thromb Res 2002;108:151-60.. PubMed
  21. Fong KC, Kinnear PE. Retrobulbar haemorrhage associated with chronic Ginkgo biloba ingestion. Postgrad Med J 2003;79:531-2..
  22. Gurley BJ, Gardner SF, Hubbard MA, et al. Cytochrome P450 phenotypic ratios for predicting herb-drug interactions in humans. Clin Pharmacol Ther 2002;72:276-87.. PubMed
  23. Kang BJ, Lee SJ, Kim MD, Cho MJ. A placebo-controlled, double-blind trial of Ginkgo biloba for antidepressant-induced sexual dysfunction. Hum Psychopharmacol 2002;17:279-84.
  24. Yale SH, Glurich I. Analysis of the inhibitory potential of Ginkgo biloba, Echinacea purpurea, and Serenoa repens on the metabolic activity of cytochrome P450 3A4, 2D6, and 2C9. J Altern Complement Med 2005;11:433-9.
  25. Yasui-Furukori N, Furukori H, Kaneda A, et al. The effects of Ginkgo biloba extracts on the pharmacokinetics and pharmacodynamics of donepezil. J Clin Pharmacol 2004;44:538-42.
  26. Markowitz JS, Donovan JL, Lindsay DeVane C, et al. Multiple-dose administration of Ginkgo biloba did not affect cytochrome P-450 2D6 or 3A4 activity in normal volunteers. J Clin Psychopharmacol 2003;23:576-81. PubMed
  27. Arenz A, Kelin M, Flehe K, et al. Occurrence of neurotoxic 4'-O-methylpyridoxine in ginkgo biloba leaves, ginkgo medications and Japanese ginkgo food. Planta Med 1996;62:548-51.
  28. Engelsen J, Nielsen JD, Winther K. Effect of coenzyme Q10 and Ginkgo biloba on warfarin dosage in stable, long-term warfarin treated outpatients. A randomised, double blind, placebo-crossover trial. Thromb Haemost 2002;87:1075-6. DOI
  29. Gaudineau C, Beckerman R, Welbourn S, Auclair K. Inhibition of human P450 enzymes by multiple constituents of the Ginkgo biloba extract. Biochem Biophys Res Comm 2004;318:1072–8. PubMed
  30. Kohler S, Funk P, Kieser M. Influence of a 7-day treatment with Ginkgo biloba special extract EGb 761 on bleeding time and coagulation: a randomized, placebo-controlled, double-blind study in healthy volunteers. Blood Coagul Fibrinolysis 2004;15:303–9. PubMed
  31. Jiang X, Williams KM, Liauw WS, et al. Effect of ginkgo and ginger on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects. Br J Clin Pharmacol 2005;59:425-32. PubMed
  32. Destro MW, Speranzini MB, Cavalheiro Filho C, et al. Bilateral haematoma after rhytidoplasty and blepharoplasty following chronic use of Ginkgo biloba. Br J Plast Surg 2005;58:100-1. PubMed
  33. Yin OQ, Tomlinson B, Waye MM, et al. Pharmacogenetics and herb-drug interactions: experience with Ginkgo biloba and omeprazole. Pharmacogenetics 2004;14:841-50. PubMed
  34. Bent S, Goldberg H, Padula A, Avins AL. Spontaneous bleeding associated with Ginkgo biloba: a case report and systematic review of the literature. J Gen Intern Med 2005;20;657-61. DOI
  35. Meisel C, Johne A, Roots I. Fatal intracerebral mass bleeding associated with Ginkgo biloba and ibuprofen. Atherosclerosis 2003;167:367. PubMed
  36. Bebbington A, Kulkarni R, Roberts P. Ginkgo biloba: Persistent bleeding after total hip arthroplasty caused by herbal self-medication. J Arthroplasty 2005;20:125-6. .
  37. Kupiec T, Raj V. Fatal seizures due to potential herb-drug interactions with Ginkgo biloba. J Anal Toxicol 2005:755-8. PubMed
  38. Hauser D, Gayowski T, Singh N. Bleeding complications precipitated by unrecognized Gingko biloba use after liver transplantation. Transpl Int 2002;15:377-9. DOI
  39. Mohutsky MA, Anderson GD, Miller JW, Elmer GW. Ginkgo biloba: evaluation of CYP2C9 drug interactions in vitro and in vivo. Am J Ther 2006;13:24-31. PubMed
  40. Kudolo GB. The effect of 3-month ingestion of Ginkgo biloba extract (EGb 761) on pancreatic beta-cell function in response to glucose loading in individuals with non-insulin-dependent diabetes mellitus. J Clin Pharmacol 2001;41:600-11.
  41. Pennisi RS. Acute generalised exanthematous pustulosis induced by the herbal remedy Ginkgo biloba. Med J Aust 2006;184:583-4. PubMed
  42. Yagmur E, Piatkowski A, Groger A, et al. Bleeding complication under Gingko biloba medication. Am J Hematol 2005;79:343-4. PubMed
  43. Vale S. Subarachnoid haemorrhage associated with Ginkgo biloba. Lancet 1998;352:36. PubMed
  44. Aruna D, Naidu MU. Pharmacodynamic interaction studies of Ginkgo biloba with cilostazol and clopidogrel in healthy human subjects. Br J Clin Pharmacol 2007;63:333-8.
  45. Dugoua JJ, Mills E, Perri D, Koren G. Safety and efficacy of ginkgo (Ginkgo biloba) during pregnancy and lactation. Can J Clin Pharmacol 2006;13:e277-84.
  46. Jiang X, Blair EY, McLachlan AJ. Investigation of the effects of herbal medicines on warfarin response in healthy subjects: a population pharmacokinetic-pharmacodynamic modeling approach. J Clin Pharmacol 2006;46:1370-8. PubMed
  47. Woelk H, Arnoldt KH, Kieser M, Hoerr R. Ginkgo biloba special extract EGb 761 in generalized anxiety disorder and adjustment disorder with anxious mood: a randomized, double-blind, placebo-controlled trial. J Psychiatr Res 2007;41:472-80. PubMed
  48. DeKosky ST, Williamson JD, Fitzpatrick AL, et al. Ginkgo biloba for prevention of dementia. JAMA 2008;300:2253-62.
  49. Dodge HH, Zitzelberger T, Oken BS, et al. A randomized placebo-controlled trial of ginkgo biloba for the prevention of cognitive decline. Neurology 2008;70(19 Pt 2):1809-17. PubMed
  50. Wiegman DJ, Brinkman K, Franssen EJ. Interaction of Ginkgo biloba with efavirenz. AIDS 2009;23:1184-5. PubMed
  51. Kim BH, Kim KP, Lim KS, et al. Influence of Ginkgo biloba extract on the pharmacodynamic effects and pharmacokinetic properties of ticlopidine: An open-label, randomized, two-period, two-treatment, two-sequence, single-dose crossover study in healthy Kor
  52. Salehi B, Imani R, Mohammadi MR, et al. Ginkgo biloba for attention-deficit/hyperactivity disorder in children and adolescents: a double blind, randomized controlled trial. Prog Neuropsychopharmacol Biol Psychiatry 2010;34:76-80. PubMed
  53. Kellermann AJ, Kloft C. Is there a risk of bleeding associated with standardized ginkgo biloba extract therapy? A systematic review and meta-analysis. Pharmacotherapy 2011;31:490-502.
  54. Kuller LH, Ives DG, Fitzpatrick AL, et al. Does Ginkgo biloba reduce the risk of cardiovascular events? Circ Cardiovasc Qual Outcomes 2010;3:41-7.
  55. Naccarato M, Yoong D, Gough K. A potential drug-herbal interaction between Ginkgo biloba and efavirenz. J Int Assoc Physicians AIDS Care (Chic). 2012;11(2):98-100. doi: 10.1177/1545109711435364. Epub 2012 Feb 9.
  56. Engelsen, J., Nielsen, J. D., and Hansen, K. F. [Effect of Coenzyme Q10 and Ginkgo biloba on warfarin dosage in patients on long-term warfarin treatment. A randomized, double-blind, placebo-controlled cross-over trial]. Ugeskr.Laeger 4-28-2003;165(18):18
  57. Parsad, D., Pandhi, R., and Juneja, A. Effectiveness of oral Ginkgo biloba in treating limited, slowly spreading vitiligo. Clin Exp.Dermatol. 2003;28(3):285-287.
  58. Bal Dit, Sollier C., Caplain, H., and Drouet, L. No alteration in platelet function or coagulation induced by EGb761 in a controlled study. Clin Lab Haematol. 2003;25(4):251-253. PubMed
  59. Yoshioka, M., Ohnishi, N., Koishi, T., Obata, Y., Nakagawa, M., Matsumoto, T., Tagagi, K., Takara, K., Ohkuni, T., Yokoyama, T., and Kuroda, K. Studies on interactions between functional foods or dietary supplements and medicines. IV. Effects of ginkgo b
  60. Yoshioka, M., Ohnishi, N., Sone, N., Egami, S., Takara, K., Yokoyama, T., and Kuroda, K. Studies on interactions between functional foods or dietary supplements and medicines. III. Effects of ginkgo biloba leaf extract on the pharmacokinetics of nifedipi
  61. Lovera, J., Bagert, B., Smoot, K., Morris, C. D., Frank, R., Bogardus, K., Wild, K., Oken, B., Whitham, R., and Bourdette, D. Ginkgo biloba for the improvement of cognitive performance in multiple sclerosis: a randomized, placebo-controlled trial. Mult.S PubMed
  62. Lin, Y. Y., Chu, S. J., and Tsai, S. H. Association between priapism and concurrent use of risperidone and Ginkgo biloba. Mayo Clin Proc 2007;82(10):1289-1290.
  63. Robertson, S. M., Davey, R. T., Voell, J., Formentini, E., Alfaro, R. M., and Penzak, S. R. Effect of Ginkgo biloba extract on lopinavir, midazolam and fexofenadine pharmacokinetics in healthy subjects. Curr Med Res Opin 2008;24(2):591-599. PubMed
  64. Penzak, S. R., Busse, K. H., Robertson, S. M., Formentini, E., Alfaro, R. M., and Davey, R. T., Jr. Limitations of using a single postdose midazolam concentration to predict CYP3A-mediated drug interactions. J Clin Pharmacol 2008;48(6):671-680. PubMed
  65. May, B. H., Yang, A. W., Zhang, A. L., Owens, M. D., Bennett, L., Head, R., Cobiac, L., Li, C. G., Hugel, H., Story, D. F., and Xue, C. C. Chinese herbal medicine for Mild Cognitive Impairment and Age Associated Memory Impairment: a review of randomised
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Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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