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Dietary supplement

Formula 594 Ingredients & Drug Interactions

by DC

Formula 594 label
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Capsule Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Formula 594 against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Formula 594 is a dietary supplement by DC with 4 active ingredients. Its ingredients are commonly taken for erectile dysfunction, low libido, fatigue and low energy.Based on those ingredients, 1,434 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ginkgo biloba, Horny Goat Weed, Mucuna pruriens. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Formula 594 by DC

Ask about any prescription or over-the-counter medication and we check it for interactions with Formula 594 by DC — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Formula 594 by DC

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

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

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 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Formula 594 contains 4 active ingredients: Horny Goat Weed, Maca, Mucuna pruriens (also called Cowhage), and Ginkgo biloba. Horny Goat Weed and Maca are traditionally used for sexual function and energy.

Mucuna pruriens is a bean containing levodopa, a compound that affects dopamine levels in the brain. Ginkgo biloba is derived from a tree leaf and has been studied for cognition and blood flow.

The product also contains inactive ingredients—gelatin, vegetable cellulose, vegetable magnesium stearate, and silica—which serve as the capsule shell and flow agents.

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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Moderate

Some clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Anxiety — rated "Possibly Effective" (Ginkgo) (Natural Medicines).
  • On file: Dementia — rated "Possibly Effective" (Ginkgo) (Natural Medicines).
  • On file: Hearing loss — rated "Possibly Effective" (Ginkgo) (Natural Medicines).
  • On file: Premenstrual syndrome (PMS) — rated "Possibly Effective" (Ginkgo) (Natural Medicines).
  • On file: Schizophrenia — rated "Possibly Effective" (Ginkgo) (Natural Medicines).

The evidence for what this product is meant to do is limited. Horny Goat Weed, Maca, and Mucuna pruriens all lack sufficient reliable evidence in our data to rate their effectiveness for sexual function, osteoporosis, or other claimed uses.

Ginkgo biloba has stronger data: it's rated possibly effective for hearing loss, stroke recovery, schizophrenia, premenstrual syndrome, dementia, and anxiety. However, for the specific conditions or goals you're considering this product for, you may want to discuss the evidence with your pharmacist or doctor.

The evidence, ingredient by ingredient Horny Goat Weed Maca Cowhage Ginkgo

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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Horny Goat Weed is generally well tolerated when used short-term, but human safety data is limited and quality varies between products. The most common side effects are dizziness, dry mouth, nosebleed, thirst, and vomiting.

Long-term use has been linked to vomiting, dry mouth, thirst, and nosebleed. One case reported a heart rhythm problem (tachyarrhythmia) after two weeks, though it's unclear if this was due to horny goat weed alone.

Mucuna pruriens most commonly causes diarrhea, flatulence, and mouth irritation when taken by mouth; in clinical studies, nausea, abdominal bloating, and vomiting occurred at higher doses. Insomnia was reported in about 3% of study participants.

Maca is generally well tolerated as a food but long-term supplement safety hasn't been studied; fresh, uncooked maca may cause stomach pain. Ginkgo is generally well tolerated for up to six years, with dizziness and gastrointestinal upset as the most common side effects, but it may increase bleeding risk and has rare reports of heart rhythm problems and spontaneous bleeding, especially in people with other bleeding risk factors.

Side effects, ingredient by ingredient Horny Goat Weed Maca Cowhage Ginkgo

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?
  • 3 of the 4 matched ingredients can interact with medications — Ginkgo, Horny Goat Weed, Cowhage.
  • 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; Parkinson's medications.
  • For scale: 1,435 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 Formula 594, check with your pharmacist if you take monoamine oxidase inhibitors (MAOIs)—a Major-severity interaction—or methyldopa, guanethidine, antidiabetes drugs, antipsychotics, tricyclic antidepressants, or certain anesthetics used in surgery. Also check if you take blood pressure medications, blood thinners like warfarin, estrogen or hormonal birth control, simvastatin, alprazolam, trazodone, efavirenz, rosiglitazone, or tacrolimus, as Moderate-severity interactions are documented.

Altogether, these interactions span 1,418 individual medications.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

Formula 594 combines four botanical ingredients with limited to modest evidence and several significant medication interactions—especially with blood pressure drugs, blood thinners, antidepressants, and diabetes medications. If you take any prescription medication, check it against your ingredients with the tool on this page before starting.

Talk to your pharmacist or doctor about whether this product is right for you and whether the evidence supports what you're hoping it will do.

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

Assessment coverage: 4 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 16, 2022.

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 Formula 594, straight from the product label.

Brand DC
Barcode (UPC) 052301594603
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jun 16, 2022
DSLD ID 266945
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free
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 Formula 594 by DC, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
30
UPC/BARCODE
052301594603
IngredientAmount% DV
Horny Goat Weed500 mg--
Maca250 mg--
Mucuna pruriens33.4 mg--
Ginkgo biloba100 mg--

Other ingredients: Gelatin, Vegetable Cellulose, Vegetable Magnesium Stearate, Silica

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.
Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, take 2 capsules daily with a meal. For a more immediate response take 3 to 4 capsules 90 minutes before activity.

Precautions

Tamper Evident: Do not use this product if imprinted foil seal under cap is broken or missing.

Keep out of reach of children.

Caution: If you are pregnant or nursing do not take this product.

Formulation

Mfg. in an FDA Registered Facility using Good Manufacturing Practices (GMPs)

Conforms to USP <2091> for weight. Meets USP <2040> disintegration for maximum bioavailability.

Gluten free

Dynamic complex

Made in USA

Storage

Keep tightly closed. Store at room temperature: 59 degrees - 86 degrees F (15 degrees to 30 degrees C).

Seals/Symbols

Quali Pure

FDA Statement of Identity

Dietary Supplement

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Formula 594 by DC label

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

Formula 594 label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Formula 594 by DC

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container30 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.

Horny Goat Weed

Interacts with
963 drugs
500 mg per serving Form: Icariin

Horny goat weed (Epimedium) is a traditional Chinese herb most often marketed for low libido and erectile problems, but solid human evidence for these...

Horny Goat Weed monograph & interactions

Maca

No known
interactions
250 mg per serving Form: Glucosinolates

Maca is a nutrient-rich Andean root often used for energy, libido, and menopause symptoms. Early studies suggest it may modestly help sexual desire an...

Maca monograph & interactions

Mucuna pruriens

Interacts with
193 drugs
33.4 mg per serving Form: L-Dopa

Cowhage (Mucuna pruriens) is a tropical legume best known as a natural source of L-dopa, the compound the body turns into dopamine. It is most studied...

Mucuna pruriens monograph & interactions

Ginkgo biloba

Interacts with
1,266 drugs
100 mg per serving Form: Glycosides, Lactones

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 monograph & interactions

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

Interaction report

Formula 594 by DC Drug Interactions

Want to check YOUR meds against Formula 594?

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
1,434Drugs
18 Major 1,416 Moderate

Ingredients driving the most interactions

Ginkgo biloba 1,266
Horny Goat Weed 963
Mucuna pruriens 193

Individual Drug Interactions

The ingredients in Formula 594 interact with 1,434 drugs. Click any drug to see the details.

3 of the 4 ingredients in Formula 594 interact with drugs. Each result below shows which ingredient is responsible. Ginkgo biloba Horny Goat Weed Mucuna pruriens

Each ingredient & the kinds of drugs it affects

For each ingredient in Formula 594 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 biloba23 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
Ginkgo biloba full monograph & interactions

Horny Goat Weed6 drug types · 963 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, horny goat weed might increase the risk of bleeding.
In vitro research and animal research shows that horny goat weed can inhibit platelet aggregation and thrombus formation. This effect has not been reported in humans.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, horny goat weed might increase the risk of hypotension.
Laboratory research suggests that horny goat weed might have hypotensive effects. This effect has not been reported in humans.

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

Theoretically, horny goat weed might increase the effects and side effects of CYP1A2 substrates.
In vitro, horny goat weed leaf extract inhibits CYP1A2. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, horny goat weed might increase the effects and side effects of CYP2B6 substrates.
In vitro, horny goat weed leaf extract inhibits CYP2B6. This effect has not been reported in humans.

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

Theoretically, horny goat weed might increase the effects and side effects of CYP3A4 substrates.
In vitro, horny goat weed extract inhibits CYP3A4 and suppresses CYP3A4 mRNA expression. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, concomitant use of horny goat weed with estrogens might increase their therapeutic and adverse effects.
In vitro evidence suggests that horny goat weed has estrogenic activity. In clinical research, horny goat weed has been shown to increase blood levels of estrogen in some females.

Likelihood Possible Evidence D
Horny Goat Weed full monograph & interactions

Mucuna pruriens8 drug types · 193 drugs

Levodopa

Concomitant use can increase the risk of levodopa-related adverse effects.
Cowhage contains levodopa. Some cowhage products have been standardized to contain 75-400 mg of levodopa per dose.

Likelihood Likely Evidence D
Methyldopa (Aldomet)

Theoretically, concomitant use of cowhage and methyldopa might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with methyldopa might cause additive hypotension. In addition, methyldopa may inhibit peripheral decarboxylation of levodopa and increase levodopa levels in the central nervous system; avoid using.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use of cowhage and non-selective MAOIs might increase the risk of hypertensive crisis.
Cowhage contains levodopa. Use of levodopa with non-selective MAOIs might cause hypertensive crisis. However, this interaction has not been reported with MAO-B selective inhibitors such as selegiline.

Likelihood Probable Evidence D
Anesthesia

Theoretically, concomitant use of cowhage and anesthesia might increase the risk of arrhythmias.
Cowhage contains levodopa. Use of levodopa with cyclopropane or halogenated hydrocarbon anesthesia has led to arrhythmias. Other anesthetics have not been implicated. Use other anesthetics in patients taking cowhage or tell patients to stop taking cowhage at least 2 weeks before surgery.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of cowhage and antidiabetes drugs might increase the risk of hypoglycemia.
Animal research shows that cowhage might have hypoglycemic effects.

Likelihood Possible Evidence D
Antipsychotic Drugs

Theoretically, use of cowhage might decrease the clinical effects of antipsychotic drugs.
Cowhage contains levodopa. Use of levodopa might counteract the antidopaminergic effects of antipsychotic medications.

Likelihood Possible Evidence D
Guanethidine (Ismelin)

Theoretically, concomitant use of cowhage and guanethidine might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with guanethidine might cause additive hypotension; avoid using.

Likelihood Probable Evidence D
Tricyclic Antidepressants (Tcas)

Theoretically, use of TCAs might reduce the levels and clinical effects of cowhage.
Cowhage contains levodopa. Use of TCAs might reduce the absorption of levodopa. Some case reports describe patients that developed hypertension and dyskinesia when taking both levodopa and TCAs.

Likelihood Possible Evidence D
Mucuna pruriens full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Formula 594, from the product label.

DC

See all DC products
Name
Dee Cee Laboratories, Inc.
Street Address
304 Dee Cee Rd.
City
White House
State
TN
ZipCode
37188
Pharmacist Counseling Corner

Formula 594 by DC: Common Questions

Does Formula 594 by DC interact with any medications?
Yes. Based on its ingredients, Formula 594 has a known interaction with 1,434 medications, including 18 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Formula 594 contains 4 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.
Is this safe during pregnancy?
No. Horny Goat Weed and Ginkgo are both rated possibly unsafe in pregnancy due to insufficient safety data and potential effects. Mucuna pruriens should be avoided because it contains levodopa, which has dopamine effects that aren't safe in pregnancy. Maca also lacks enough safety data in supplement amounts. Talk with your doctor before taking any of these ingredients if you're pregnant or planning to become pregnant.
What about breastfeeding?
Safety hasn't been established for any of these ingredients while breastfeeding. Mucuna pruriens is of particular concern because levodopa can lower prolactin levels and reduce milk supply. If you're breastfeeding, speak with your pharmacist or doctor before starting this product.
Does this product actually work for sexual function?
Horny Goat Weed and Maca both lack sufficient reliable evidence in our data to say whether they work for sexual dysfunction. Mucuna pruriens contains levodopa, which affects dopamine, but evidence for it is also insufficient to rate. If sexual function is your goal, your doctor can discuss what the research actually supports.
What's Mucuna pruriens and why is it in here?
Mucuna pruriens is a bean that naturally contains levodopa, a compound that raises dopamine levels in the brain. It's included for potential energy and mood effects, but because it's an active drug-like substance, it needs careful use and professional guidance—especially if you take any psychiatric or blood pressure medications.
Are there any fillers in this?
Yes. Besides the four active ingredients, the capsule contains gelatin, vegetable cellulose, vegetable magnesium stearate, and silica as inactive ingredients to form and fill the capsule.
What side effects might I experience?
Horny Goat Weed may cause dizziness, dry mouth, nosebleed, thirst, or vomiting. Mucuna pruriens commonly causes diarrhea, gas, and mouth irritation; nausea and bloating can occur at higher doses, and about 3% of study participants reported insomnia. Maca may cause stomach pain if fresh and uncooked. Ginkgo typically causes dizziness and stomach upset but carries a small risk of increased bleeding and, rarely, heart rhythm problems.

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.

Formula 594 label
Go deeper

The Full Monographs Behind Formula 594’s Ingredients

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

Herb & supplement monograph

Horny Goat Weed

Interacts with 963 drugs

Horny goat weed (Epimedium) is a traditional Chinese herb most often marketed for low libido and erectile problems, but solid human evidence for these uses is lacking. While short-term use s...

Read the full Horny Goat Weed monograph → Herb & supplement monograph

Maca

Maca is a nutrient-rich Andean root often used for energy, libido, and menopause symptoms. Early studies suggest it may modestly help sexual desire and some menopause symptoms, but the evide...

Read the full Maca monograph → Herb & supplement monograph

Cowhage

Interacts with 193 drugs

Cowhage (Mucuna pruriens) is a tropical legume best known as a natural source of L-dopa, the compound the body turns into dopamine. It is most studied for Parkinson's disease symptoms and ma...

Read the full Cowhage monograph → Herb & supplement monograph

Ginkgo

Interacts with 1,266 drugs

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 generally weak, and it is not proven to...

Read the full Ginkgo monograph →
Sources

Sources & How We Checked

Formula 594'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 121 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.

Horny Goat Weed 11 references
  1. Cirigliano MD, Szapary PO. Horny goat weed for erectile dysfunction. Alt Med Alert 2001;4:19-22.
  2. Partin JF, Pushkin YR. Tachyarrhythmia and hypomania with horny goat weed. Psychosomatics 2004;45:536-7. PubMed
  3. De Naeyer A, Pocock V, Milligan S, De Keukeleire D. Estrogenic activity of a polyphenolic extract of the leaves of Epimedium brevicornum. Fitoterapia 2005;76:35-40. PubMed
  4. Zhang CZ, Wang SX, Zhang Y, et al. In vitro estrogenic activities of Chinese medicinal plants traditionally used for the management of menopausal symptoms. J Ethnopharmacol 2005;98:295-300. PubMed
  5. Yap SP, Shen P, Li J, et al. Molecular and pharmacodynamic properties of estrogenic extracts from the traditional Chinese medicinal herb, Epimedium. J Ethnopharmacol 2007;113:218-24. PubMed
  6. Yan, F. F., Liu, Y., Liu, Y. F., and Zhao, Y. X. Herba Epimedii water extract elevates estrogen level and improves lipid metabolism in postmenopausal women. Phytother.Res. 2008;22(9):1224-1228. PubMed
  7. Ramanathan VS, Mitropoulos E, Shlopov B, et al. An Enzyte'ing' case of acute hepatitis. J Clin Gastroenterol 2011;45(9):834-5. PubMed
  8. Zhong Q, Shi Z, Zhang L, et al. The potential of Epimedium koreanum Nakai for herb-drug interaction. J Pharm Pharmacol 2017;69(10):1398-408. doi: 10.1111/jphp.12773.
  9. Irfan M, Kwon TH, Lee DH, et al. Antiplatelet and Antithrombotic Effects of Epimedium koreanum Nakai. Evid Based Complement Alternat Med. Apr 2021;2021:7071987. PubMed
  10. Tan K, Yang W, Pang L, Hou F. Differences in clinical characteristics among 726 patients with Chinese herbal medicine- or Western medicine-induced liver injury. Medicine (Baltimore) 2022;101(32):e29909. PubMed
  11. Li K, Yu XH, Maskey AR, et al. Cytochrome P450 3A4 suppression by epimedium and active compound kaempferol leads to synergistic anti-inflammatory effect with corticosteroid. Front Pharmacol 2023;13:1042756. PubMed

See these in context on the Horny Goat Weed monograph →

Maca 1 reference
  1. Valerio, L. G., Jr. and Gonzales, G. F. Toxicological aspects of the South American herbs cat's claw (Uncaria tomentosa) and Maca (Lepidium meyenii) : a critical synopsis. Toxicol.Rev 2005;24(1):11-35. PubMed

See these in context on the Maca monograph →

Cowhage 12 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Anon. Epidemiological notes and reports: Mucuna pruriens-associated pruritus--New Jersey. MMWR Morb Mortal Wkly Rep 1985;34:732-3.
  4. HP-200 in Parkinson's Disease study group. An alternative medicine treatment for Parkinson's disease: Results of a multicenter clinical trial. J Alt Comp Med 1995;1:249-55. DOI
  5. Infante ME, Perez AM, Simao MR, et al. Outbreak of acute toxic psychosis attributed to Mucuna pruriens. Lancet 1990;336:1129. PubMed
  6. Vaidya AB, Rajagopalan TG, Mankodi NA, et al. Treatment of Parkinson's disease with the cowhage plant-Mucuna pruriens Bak. Neurol India 1978;26:171-6.
  7. Vadivel V, Janardhanan K. Nutritional and anti-nutritional composition of velvet bean: an under-utilized food legume in south India. Int J Food Sci Nutr 2000;51:279-87. PubMed
  8. Akhtar MS, Qureshi AQ, Iqbal J. Antidiabetic evaluation of Mucuna pruriens, Linn seeds. J Pak Med Assoc 1990;40:147-50.
  9. Prakash, D., Niranjan, A., and Tewari, S. K. Some nutritional properties of the seeds of three Mucuna species. Int.J.Food Sci.Nutr. 2001;52(1):79-82.
  10. Vadivel, V. and Janardhanan, K. Nutritional and antinutritional characteristics of seven South Indian wild legumes. Plant Foods Hum.Nutr 2005;60(2):69-75. PubMed
  11. Creapure (Creatine Monohydrate). Toxicological Datasheet. Degussa BioActives. Available at: https://www.fda.gov/ohrms/DOCKETS/.../95s-0316-rpt0154-54-Ref-50-vol112.pdf.
  12. Pulikkalpura H, Kurup R, Mathew PJ, Baby S. Levodopa in Mucuna pruriens and its degradation. Sci Rep 2015;5:11078. PubMed

See these in context on the Cowhage 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.
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  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
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  67. Lei, H. P., Wang, G., Wang, L. S., Ou-yang, D. S., Chen, H., Li, Q., Zhang, W., Tan, Z. R., Fan, L., He, Y. J., and Zhou, H. H. Lack of effect of Ginkgo biloba on voriconazole pharmacokinetics in Chinese volunteers identified as CYP2C19 poor and extensiv
  68. Russo, V., Stella, A., Appezzati, L., Barone, A., Stagni, E., Roszkowska, A., and Delle, Noci N. Clinical efficacy of a Ginkgo biloba extract in the topical treatment of allergic conjunctivitis. Eur J Ophthalmol. 2009;19(3):331-336. PubMed
  69. Fan, L., Tao, G. Y., Wang, G., Chen, Y., Zhang, W., He, Y. J., Li, Q., Lei, H. P., Jiang, F., Hu, D. L., Huang, Y. F., and Zhou, H. H. Effects of Ginkgo biloba extract ingestion on the pharmacokinetics of talinolol in healthy Chinese volunteers. Ann Phar PubMed
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  71. Singh, V., Singh, S. P., and Chan, K. Review and meta-analysis of usage of ginkgo as an adjunct therapy in chronic schizophrenia. Int J Neuropsychopharmacol. 2010;13(2):257-271.
  72. Kim, T. E., Kim, B. H., Kim, J., Kim, K. P., Yi, S., Shin, H. S., Lee, Y. O., Lee, K. H., Shin, S. G., Jang, I. J., and Yu, K. S. Comparison of the pharmacokinetics of ticlopidine between administration of a combined fixed-dose tablet formulation of ticl
  73. Nicolai, S. P., Gerardu, V. C., Kruidenier, L. M., Prins, M. H., and Teijink, J. A. From the Cochrane library: Ginkgo biloba for intermittent claudication. Vasa 2010;39(2):153-158. PubMed
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  77. Zhou, Y. and Zeng, R. [Effects of Ginkgo biloba extract on anticoagulation and blood drug level of warfarin in healthy wolunteers]. Zhongguo Zhong Yao Za Zhi 2011;36(16):2290-2293. DOI
  78. Skogh, M. Extracts of Ginkgo biloba and bleeding or haemorrhage. Lancet 10-3-1998;352(9134):1145-1146. PubMed
  79. Fessenden JM, Wittenborn W, and Clarke L. Ginkgo biloba: a case report of herbal medicine and bleeding postoperatively from a laparoscopic cholecystectomy. Am Surg 2001;67(1):33-35.
  80. Burkard G. [The efficacy and safety of ginkgo biloba extract in dementia]. Fortschr Med [Supp] 1991;109(107):6-8.
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See these in context on the Ginkgo monograph →

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.

© 2021 Therapeutic Research Center, LLC

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