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Dietary supplement

Quercetin Plus Ingredients & Drug Interactions

by True Botanica

Quercetin Plus label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Quercetin Plus 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: Moderate

Quercetin Plus is a dietary supplement by True Botanica with 6 active ingredients. Its ingredients are commonly taken for seasonal allergies, antioxidant support, heart and blood pressure health.Based on those ingredients, 1,220 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Quercetin, Fenugreek, Powder, Nettle Leaf Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Quercetin Plus by True Botanica

Ask about any prescription or over-the-counter medication and we check it for interactions with Quercetin Plus by True Botanica — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Quercetin Plus by True Botanica

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

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 4 of its 6 active ingredients.
  • “Nettle Leaf Extract” is listed as a grouped ingredient — the label gives one combined amount (100 mg) without saying how much of each component you get.
  • “Lemon/Quince Pentas Mix” is listed as a grouped ingredient — the label gives one combined amount (10 mg) without saying how much of each component you get.

Quercetin Plus contains six active ingredients. Quercetin is a plant compound (flavonoid) with limited proven benefits.

Fenugreek seed is traditionally used and shows some evidence for sexual function and blood sugar support. Silica (from silicon) has possibly effective evidence for bone health.

Lemon, Quince, and nettle leaf extract round out the formula, though their individual contributions to this product's overall purpose aren't specified in the ingredient list. The product also contains inactive ingredients — cellulose, inulin powder, and magnesium stearate — which are fillers and binders.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: healthy respiratory, cardiovascular, reproductive function.
  • We looked for evidence on: Allergic rhinitis (hay fever), Asthma, Cardiovascular disease (CVD), Hypertension, Hypercholesterolemia, Hyperlipidemia — and 4 related terms.
  • The closest evidence on file: Fenugreek is rated "Possibly Ineffective" for Benign prostatic hyperplasia (BPH) (Natural Medicines).
  • Also on file: Quercetin is rated "Insufficient Reliable Evidence To Rate" for Allergic rhinitis (hay fever), Asthma, Atherosclerosis, Benign prostatic hyperplasia (BPH), and more.

The evidence for this product as a whole is limited. Among its ingredients, Fenugreek shows the strongest data — it's possibly effective for sexual function, sexual arousal, dysmenorrhea (menstrual pain), and diabetes.

Silica is possibly effective for osteoporosis. Quince is possibly effective for acid reflux (GERD).

Quercetin is rated possibly ineffective for athletic performance, and the rest of its uses lack reliable evidence. Lemon and nettle leaf extract have insufficient evidence for the conditions listed in our data.

Without knowing the intended use of this formula, it's hard to say what to expect.

The evidence, ingredient by ingredient Quercetin Stinging Nettle Silicon Fenugreek Lemon Quince

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 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.

Fenugreek and Quercetin carry cautions about high doses and long-term use — safety at supplement doses isn't well studied. Silica is generally well tolerated from food and typical supplements, though high-dose or long-term safety is unclear.

Lemon at food amounts is safe, but medicinal amounts haven't been well studied. Quince as food is fine, but concentrated extracts lack safety data.

The most common side effects reported with fenugreek are gastrointestinal — abdominal pain, bloating, diarrhea, and nausea. Quercetin may cause headache or tingling.

Lemon juice taken in larger amounts can cause heartburn and stomach upset. Rare allergic reactions including bronchospasm and angioedema have been reported with fenugreek.

Side effects, ingredient by ingredient Quercetin Stinging Nettle Silicon Fenugreek Lemon Quince

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 3 of the 5 matched ingredients can interact with medications — Quercetin, Lemon, Fenugreek.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 1,216 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.

Check these medication types before taking this product, worst first: blood thinners (anticoagulants and antiplatelets), diabetes drugs, cholesterol drugs, blood pressure medications, anti-seizure drugs, chemotherapy agents, antifungal drugs (itraconazole), theophylline, and the antibiotic class called quinolones. All are Moderate severity except itraconazole, which is Minor.

If you take any of these, use the search tool on this page to check your specific medication.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

This product combines herbs and compounds with varying levels of evidence and multiple medication interactions. If you take a blood thinner, cholesterol drug, diabetes medication, blood pressure medication, or any regular prescription, check it against our tool before starting.

Talk to your pharmacist or doctor about whether this product fits your health goals and is safe alongside what you're already taking.

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

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 22, 2025.

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 Quercetin Plus, straight from the product label.

Brand True Botanica
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Aug 22, 2025
DSLD ID 336239
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), No Allergies, Gluten Free, Dairy 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 Quercetin Plus by True Botanica, 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
IngredientAmount% DV
Silica1 mg--
Lemon0 NP--
Quercetin500 mg--
Nettle Leaf Extract100 mg--
Fenugreek, Powder15 mg--
Quince0 NP--
BD Oak Bark Pentas Mix10 mg--
Lemon/Quince Pentas Mix10 mg--

Other ingredients: Cellulose, Inulin, Powder, Magnesium Stearate

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.
Formulation

This unique herbal blend promotes a healthy function of the respiratory, cardiovascular and reproductive system.

Contains no milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, sesame, or soybeans. Gluten free.

Vegetarian capsules.

High potency - multi-functional

Suggested/Recommended/Usage/Directions

Best results if taken with meals.

Suggested usage: Two capsules once daily, or as suggested by your health care provider.

Precautions

Contact your health care provider before using this product if you are pregnant, lactating or have other medical concerns or compatibility issues.

Do not use this product if allergies to the listed ingredients are known to exist or if any adverse effects result after taking the first dose.

This product contains a desiccant package, which should not be eaten.

Keep out of the reach of children.

Storage

This product contains a desiccant package, which should not be eaten. Keep desiccant in the bottle until all tablets have been taken.

FDA Disclaimer Statement

These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

FDA Statement of Identity

A Dietary Supplement

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

See for yourself

Quercetin Plus by True Botanica label

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

Quercetin Plus 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 Quercetin Plus by True Botanica

These are the 6 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.

Quercetin

Interacts with
1,169 drugs
500 mg per serving Form: Quercetin Dihydrate

Quercetin is a plant flavonoid with antioxidant and anti-inflammatory properties found in many common foods and sold as a supplement. While early rese...

Quercetin monograph & interactions

Nettle Leaf Extract

Interacts with
164 drugs
100 mg per serving

Stinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence...

Nettle Leaf Extract monograph & interactions

Fenugreek, Powder

Interacts with
389 drugs
15 mg per serving

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. So...

Fenugreek, Powder monograph & interactions

BD Oak Bark Pentas Mix

10 mg per serving

Lemon/Quince Pentas Mix

10 mg per serving

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

Interaction report

Quercetin Plus by True Botanica Drug Interactions

Want to check YOUR meds against Quercetin Plus?

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
1,220Drugs
1,220 Moderate

Ingredients driving the most interactions

Quercetin 1,169
Fenugreek, Powder 389
Nettle Leaf Extract 164
Lemon 1

Individual Drug Interactions

The ingredients in Quercetin Plus interact with 1,220 drugs. Click any drug to see the details.

4 of the 6 ingredients in Quercetin Plus interact with drugs. Each result below shows which ingredient is responsible. Quercetin Fenugreek, Powder Nettle Leaf Extract Lemon

Each ingredient & the kinds of drugs it affects

For each ingredient in Quercetin Plus 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.

Quercetin21 drug types · 1,169 drugs

Antidiabetes Drugs

Theoretically, concomitant use of quercetin and antidiabetes drugs might increase the risk of hypoglycemia.

Clinical research suggests that a combination of quercetin, myricetin, and chlorogenic acid reduce levels of fasting glucose in patients with type 2 diabetes, including those already taking antidiabetes agents. The effect of quercetin alone is unknown.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.

Quercetin can modestly decrease blood pressure in people with mild hypertension. Theoretically, it might have additive blood pressure lowering effects when used with antihypertensive drugs.

Likelihood Possible Evidence B
Cyclosporine (Neoral, Sandimmune)

Theoretically, concomitant use might increase the levels and adverse effects of cyclosporine.

A small study in healthy volunteers shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of a single dose of cyclosporine, possibly due to inhibition of p-glycoprotein or cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporin.

Likelihood Possible Evidence B
Cytochrome P450 2C8 (Cyp2C8) Substrates

Theoretically, concomitant use might increase the levels and adverse effects of CYP2C8 substrates.

In vitro research shows that quercetin inhibits CYP2C8. Inhibition of paclitaxel (Taxol) metabolism via CYP2C8 has been reported in vitro. However, a small study in humans found no effect of quercetin on rosiglitazone (Avandia), which is also a CYP2C8 substrate.

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

Theoretically, concomitant use might increase the levels and adverse effects of CYP2C9 substrates.

A small clinical study in healthy volunteers shows that taking quercetin 500 mg twice daily for 10 days prior to taking diclofenac, a CYP2C9 substrate, increases diclofenac plasma levels by 75% and prolongs the half-life by 32.5%. Animal research also shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of losartan (Cozaar), a substrate of CYP2C9. Furthermore, laboratory research shows that quercetin inhibits CYP2C9.

Likelihood Possible Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, concomitant use might increase the levels and adverse effects of CYP2D6 substrates.

In vitro research show that quercetin inhibits CYP2D6. This effect has not been reported in humans.

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

Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
A small clinical study in healthy volunteers shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of a single dose of cyclosporine (Neoral, Sandimmune), a substrate of CYP3A4. Animal research also shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of losartan (Cozaar) and quetiapine (Seroquel), substrates of CYP3A4. Other laboratory research also shows that quercetin inhibits CYP3A4. However, one clinical study shows that quercetin can increase the metabolism of midazolam, a substrate of CYP3A4, and decrease serum concentrations of midazolam by about 24% in some healthy individuals, suggesting possible induction of CYP3A4.

Likelihood Possible Evidence D
Diclofenac (Voltaren, Others)

Theoretically, concomitant use might increase the levels and adverse effects of diclofenac.

A small clinical study in healthy volunteers shows that taking quercetin 500 mg twice daily for 10 days prior to taking diclofenac increases diclofenac plasma levels by 75% and prolongs the half-life by 32.5%. This is thought to be due to inhibition of CYP2C9 by quercetin.

Likelihood Probable Evidence B
Losartan (Cozaar)

Theoretically, concomitant use might increase the effects and adverse effects of losartan and decrease the effects of its active metabolite.

Animal research shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of losartan (Cozaar) while decreasing plasma levels of losartan's active metabolite. This metabolite, which is around 10-fold more potent than losartan, is the result of cytochrome P450 (CYP) 2C9- and CYP3A4-mediated transformation of losartan. Additionally, in vitro research shows that quercetin may inhibit P-glycoprotein-mediated efflux of losartan from the intestines, resulting in increased absorption of losartan. These results suggest that concomitant use of quercetin and losartan might increase systemic exposure to losartan while also decreasing plasma concentrations of losartan's active and more potent metabolite.

Likelihood Possible Evidence D
Midazolam (Versed)

Theoretically, concomitant use might decrease the levels and effects of midazolam.

A small clinical study in healthy volunteers shows that quercetin can increase the metabolism of midazolam, with a decrease in AUC of about 24%.

Likelihood Possible Evidence B
Mitoxantrone

Theoretically, quercetin might increase the effects and adverse effects of mitoxantrone.
In vitro research shows that quercetin increases the intracellular accumulation and cytotoxicity of mitoxantrone, possibly through inhibition of breast cancer resistance protein (BCRP), of which mitoxantrone is a substrate. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Organic Anion Transporter 1 (Oat1) Substrates

Theoretically, concomitant use might increase the effects and adverse effects of OAT1 substrates.

In vitro research shows that quercetin is a strong non-competitive inhibitor of OAT1, with half-maximal inhibitory concentration (IC50) values less than 10 mcM. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Organic Anion Transporter 3 (Oat3) Substrates

Theoretically, concomitant use might increase the effects and adverse effects of OAT3 substrates.

In vitro research shows that quercetin is a strong non-competitive inhibitor of OAT3, with half-maximal inhibitory concentration (IC50) values as low as 0.75 mcM. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, concomitant use might increase the effects and adverse effects of OATP substrates.

In vitro evidence shows that quercetin can inhibit organic anion-transporting peptide (OATP) 1B1-mediated uptake of estrone-3-sulfate and pravastatin. Furthermore, clinical research in healthy males shows that intake of quercetin along with pravastatin increases the AUC of pravastatin by 24%, prolongs its half-life by 14%, and decreases its apparent clearance by 18%, suggesting that quercetin modestly inhibits the uptake of pravastatin in hepatic cells.

Likelihood Possible Evidence B
P-Glycoprotein Substrates

Theoretically, concomitant use might alter the effects and adverse effects of P-glycoprotein substrates.

There is preliminary evidence that quercetin inhibits the gastrointestinal P-glycoprotein efflux pump, which might increase the bioavailability and serum levels of drugs transported by the pump. A small study in healthy volunteers reported that pretreatment with quercetin increased bioavailability and plasma levels after a single dose of cyclosporine (Neoral, Sandimmune). Also, two small studies have shown that quercetin might decrease the absorption of talinolol, a substrate transported by the gastrointestinal P-glycoprotein efflux pump. However, in another small study, several days of quercetin treatment did not significantly affect the pharmacokinetics of saquinavir (Invirase). The reason for these discrepancies is not entirely clear. Until more is known, use quercetin cautiously in combination with P-glycoprotein substrates.

Likelihood Possible Evidence B
Pravastatin (Pravachol)

Theoretically, concomitant use might increase the effects and adverse effects of pravastatin.
In vitro evidence shows that quercetin can inhibit OATP 1B1-mediated uptake of pravastatin. Also, preliminary clinical research in healthy males shows that intake of quercetin along with pravastatin increases the maximum concentration of pravastatin by 24%, prolongs its half-life by 14%, and decreases its apparent clearance by 18%, suggesting that quercetin modestly inhibits the uptake of pravastatin in hepatic cells.

Likelihood Possible Evidence B
Prazosin (Minipress)

Theoretically, quercetin might increase the effects and adverse effects of prazosin.
In vitro research shows that quercetin inhibits the transcellular efflux of prazosin, possibly through inhibition of breast cancer resistance protein (BCRP), of which prazosin is a substrate. BCRP is an ATP-binding cassette efflux transporter in the intestines, kidneys, and liver. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Quetiapine (Seroquel)

Theoretically, concomitant use might increase the effects and adverse effects of quetiapine.
Animal research shows that pretreatment with quercetin can increase plasma levels of quetiapine and prolong its clearance, possibly due to inhibition of cytochrome P450 3A4 (CYP3A4) by quercetin. Additionally, the brain-to-plasma ratio of quetiapine concentrations increased, possibly due to inhibition of P-glycoprotein at the blood-brain barrier. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, concomitant use might inhibit the effects of quinolone antibiotics.
In vitro, quercetin binds to the DNA gyrase site on bacteria, which may interfere with the activity of quinolone antibiotics.

Likelihood Possible Evidence B
Sulfasalazine (Azulfidine)

Theoretically, quercetin might increase the effects and adverse effects of sulfasalazine.
Animal research shows that quercetin increases the maximum serum concentration (Cmax) and area under the curve (AUC) of sulfasalazine, possibly through inhibition of breast cancer resistance protein (BCRP), of which sulfasalazine is a substrate. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, quercetin may increase the risk of bleeding if used with warfarin.
Animal and in vitro studies show that quercetin might increase serum levels of warfarin. Quercetin and warfarin have the same human serum albumin (HSA) binding site, and in vitro research shows that quercetin has stronger affinity for the HSA binding site and can theoretically displace warfarin, causing higher serum levels of warfarin. Animal research shows that taking quercetin for 2 weeks before initiating warfarin increases the maximum serum level of warfarin by 30%, the half-life by 10%, and the overall exposure by 63% when compared with control. Concomitant administration of quercetin and warfarin, without quercetin pre-treatment, also increased these measures, but to a lesser degree. Researchers theorize that inhibition of CYP3A4 by quercetin may explain these effects. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Quercetin full monograph & interactions

Fenugreek, Powder9 drug types · 389 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fenugreek might have additive effects when used with anticoagulant or antiplatelet drugs.
Some of the constituents in fenugreek have antiplatelet effects in animal and in vitro research. However, common fenugreek products might not contain sufficient concentrations of these constituents for clinical effects. A clinical study in patients with coronary artery disease or diabetes shows that taking fenugreek seed powder 2.5 grams twice daily for 3 months does not affect platelet aggregation, fibrinolytic activity, or fibrinogen levels .

Likelihood Unlikely Evidence B
Antidiabetes Drugs

Theoretically, fenugreek seed might have additive hypoglycemic effects when used with antidiabetes drugs.
Clinical research shows that fenugreek seed can reduce fasting blood glucose and 2-hour postprandial glucose levels in adults with type 2 diabetes.

Likelihood Probable Evidence B
Clopidogrel (Plavix)

Theoretically, fenugreek seed might alter the clinical effects of clopidogrel by inhibiting its conversion to the active form.
Animal research shows that fenugreek seed 200 mg/kg daily for 14 days increases the maximum serum concentration of clopidogrel by 21%. It is unclear how this affects the pharmacokinetics of the active metabolite of clopidogrel; however, this study found that concomitant use of fenugreek seed and clopidogrel prolonged bleeding time by an additional 11%.

Likelihood Possible Evidence D
Metoprolol (Toprol)

Theoretically, fenugreek seed might have additive hypotensive effects when used with metoprolol.
Animal research shows that fenugreek seed 300 mg/kg daily for 2 weeks decreases systolic and diastolic blood pressure by 9% and 11%, respectively, when administered alone, and by 15% and 22%, respectively, when given with metoprolol 10 mg/kg.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, fenugreek might decrease plasma levels of phenytoin.
Animal research shows that taking fenugreek seeds for 1 week decreases maximum concentrations and the area under the curve of a single dose of phenytoin by 44% and 72%, respectively. This seems to be related to increased clearance. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and fenugreek might reduce levels and therapeutic effects of sildenafil.
Animal research shows that taking fenugreek seeds for 1 week reduces maximum concentrations and the area under the curve of a single dose of sildenafil by 27% and 48%, respectively. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Theophylline

Theoretically, fenugreek may reduce the levels and clinical effects of theophylline.
Animal research shows that fenugreek 50 grams daily for 7 days reduces the maximum serum concentration (Cmax) of theophylline by 28% and the area under the plasma drug concentration-time curve (AUC) by 22%.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, fenugreek might have additive effects with warfarin and increase the international normalized ratio (INR).
Some fenugreek constituents have antiplatelet effects, although these might not be present in concentrations that are clinically significant. In one case report, a patient taking warfarin experienced an increased INR when starting to take fenugreek in combination with boldo.

Likelihood Possible Evidence D
Antihypertensive Drugs

Fenugreek may also have an additive effect on blood pressure-lowering medications. Studies on animals have shown that fenugreek seed can decrease both systolic and diastolic blood pressure by up to 22% when combined with metoprolol. Therefore, it is essential to monitor your blood pressure regularly if you are taking fenugreek and metoprolol together or any other antihypertensive drugs.

Likelihood Possible Evidence C
Fenugreek, Powder full monograph & interactions

Nettle Leaf Extract4 drug types · 164 drugs

Antidiabetes Drugs

Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Clinical research shows that stinging nettle might decrease blood glucose levels in patients with diabetes.

Likelihood Possible Evidence B
Diuretic Drugs

Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Animal research suggests that the above ground parts and roots of stinging nettle may have a diuretic effect.

Likelihood Possible Evidence D
Lithium

Theoretically, stinging nettle might reduce excretion and increase levels of lithium.
Animal research suggests that stinging nettle has diuretic and natriuretic properties, which could alter the excretion of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is some concern that stinging nettle might decrease the effects of anticoagulant drugs such as warfarin.
Stinging nettle contains a significant amount of vitamin K. When taken in large quantities, this might interfere with the activity of warfarin.

Likelihood Possible Evidence D
Nettle Leaf Extract full monograph & interactions

Lemon1 drug type · 1 drug

Itraconazole (Sporanox)

Theoretically, taking itraconazole capsules or tablets with a beverage containing lemon might increase the levels and clinical effects of itraconazole.
In one case report, dissolving itraconazole tablets in a small amount of specific beverages containing lemon prior to administration increased the level of itraconazole in a lung transplant patient. In this case, the increased bioavailability was desirable and was likely due to improved tablet dissolution in the acidic beverage.

Likelihood Possible Evidence D
Lemon full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Quercetin Plus, from the product label.

True Botanica

See all True Botanica products
Name
True Botanica, LLC
Street Address
1005 Richards Road, Suite D
City
Hartland
State
WI
ZipCode
53029
Phone Number
1-800-315-8783
Web Address
www.truebotanica.com
Pharmacist Counseling Corner

Quercetin Plus by True Botanica: Common Questions

Does Quercetin Plus by True Botanica interact with any medications?
Yes. Based on its ingredients, Quercetin Plus has a known interaction with 1,220 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Quercetin Plus contains 6 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 this during pregnancy?
Fenugreek is rated likely unsafe in supplement doses during pregnancy — avoid it. Quercetin and Lemon lack enough safety data, so avoid supplemental amounts. Silica is rated likely safe. Because this formula mixes unsafe and unknown ingredients, talk to your doctor or pharmacist before using it if you're pregnant.
Can I take this while breastfeeding?
Fenugreek is possibly safe while breastfeeding and is sometimes used to support milk supply, but evidence is limited — discuss with your provider first. Quercetin, Lemon, and Quince don't have enough safety data. Silica is rated likely safe. Personalized advice from your doctor or pharmacist is best here.
What's in this besides the main ingredients?
The product contains cellulose, inulin powder, and magnesium stearate as inactive ingredients — these are fillers and binders used to hold the capsule together.
Does Fenugreek in this formula help with sexual function?
Fenugreek is rated possibly effective for sexual function and sexual arousal based on the evidence we hold. That said, this product also contains other ingredients whose roles aren't specified, so the overall effect depends on how much fenugreek is in each dose and the contribution of the other herbs.
What side effects does Fenugreek cause?
The most common side effects are stomach-related: abdominal pain, bloating, diarrhea, and nausea. Rare but serious allergic reactions including bronchospasm and throat swelling have also been reported. If you experience any allergic symptoms, stop and seek medical care.
I'm on warfarin (a blood thinner). Can I take this?
No — do not take this without talking to your doctor or pharmacist first. Both Quercetin and Fenugreek in this product interact with warfarin and may increase your bleeding risk. Your healthcare provider may need to adjust your dose or monitor you closely.

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

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The Full Monographs Behind Quercetin Plus’s Ingredients

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

Herb & supplement monograph

Quercetin

Interacts with 1,169 drugs

Quercetin is a plant flavonoid with antioxidant and anti-inflammatory properties found in many common foods and sold as a supplement. While early research is interesting for allergies, blood...

Read the full Quercetin monograph → Herb & supplement monograph

Stinging Nettle

Interacts with 164 drugs

Stinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence is mixed and mostly preliminary, so it i...

Read the full Stinging Nettle monograph → Herb & supplement monograph

Silicon

Silicon is a trace mineral found in the body and in foods like oats, barley, and certain fruits and vegetables, and it is popular in supplements for hair, skin, nail, and bone health. Some s...

Read the full Silicon monograph → Herb & supplement monograph

Fenugreek

Interacts with 389 drugs

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. Some early research is encouraging for blo...

Read the full Fenugreek monograph → Herb & supplement monograph

Lemon

Interacts with 1 drug

Lemon is a common citrus fruit that is a good source of vitamin C and citric acid, and it is widely used in food, drinks, and home remedies. While it can support hydration and a healthy diet...

Read the full Lemon monograph → Herb & supplement monograph

Quince

Quince is a tart, apple-like fruit traditionally used for digestive complaints, reflux, and soothing the throat and skin. Early research is interesting but limited, so quince should not repl...

Read the full Quince monograph →
Sources

Sources & How We Checked

Quercetin Plus'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 100 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.

Silicon 19 references
  1. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  2. Jugdaohsingh R, Anderson SH, Tucker KL, et al. Dietary silicon intake and absorption. Am J Clin Nutr 2002;75:887-93. PubMed
  3. Ichiyanagi O, Sasagawa I, Adachi Y, et al. Silica urolithiasis without magnesium trisilicate intake. Urol Int 1998;61:39-42. PubMed
  4. Levison DA, Crocker PR, Banim S, Wallace DM. Silica stones in the urinary bladder. Lancet 1982;1:704-5. PubMed
  5. Lee MH, Lee YH, Hsu TH, et al. Silica stone--development due to long time oral trisilicate intake. Scand J Urol Nephrol 1993;27:267-9. PubMed
  6. Cruz Guerra, N. A., Gomez Garcia, M. A., Lovaco, Castellano F., Saez Garrido, J. C., Garcia, Cuerpo E., and Escudero, Barrilero A. [Silica urolithiasis: report of a new case]. Actas Urol.Esp 2000;24(2):202-204.
  7. Merget, R., Bauer, T., Kupper, H. U., Philippou, S., Bauer, H. D., Breitstadt, R., and Bruening, T. Health hazards due to the inhalation of amorphous silica. Arch Toxicol. 2002;75(11-12):625-634. PubMed
  8. Khuder, S. A., Peshimam, A. Z., and Agraharam, S. Environmental risk factors for rheumatoid arthritis. Rev Environ Health 2002;17(4):307-315. PubMed
  9. McLaughlin, J. K., Chow, W. H., and Levy, L. S. Amorphous silica: a review of health effects from inhalation exposure with particular reference to cancer. J Toxicol.Environ Health 4-25-1997;50(6):553-566. DOI
  10. Pelucchi, C., Pira, E., Piolatto, G., Coggiola, M., Carta, P., and La, Vecchia C. Occupational silica exposure and lung cancer risk: a review of epidemiological studies 1996-2005. Ann.Oncol. 2006;17(7):1039-1050. PubMed
  11. Gillissen, A., Gessner, C., Hammerschmidt, S., Hoheisel, G., and Wirtz, H. [Health significance of inhaled particles]. Dtsch.Med Wochenschr. 3-24-2006;131(12):639-644.
  12. Hu, J. F., Qu, H., and Wang, J. Z. [Meta analysis for relationship between exposure of free silicon dioxide and lung tumor]. Zhonghua Lao.Dong.Wei Sheng Zhi.Ye.Bing.Za Zhi. 2006;24(7):415-417.
  13. Jugdaohsingh, R. Silicon and bone health. J Nutr Health Aging 2007;11(2):99-110.
  14. Lacasse, Y., Martin, S., Gagne, D., and Lakhal, L. Dose-response meta-analysis of silica and lung cancer. Cancer Causes Control 2009;20(6):925-933. PubMed
  15. McCormic, Z. D., Khuder, S. S., Aryal, B. K., Ames, A. L., and Khuder, S. A. Occupational silica exposure as a risk factor for scleroderma: a meta-analysis. Int Arch Occup.Environ Health 2010;83(7):763-769. PubMed
  16. Haddad, F. S. and Kouyoumdjian, A. Silica stones in humans. Urol.Int 1986;41(1):70-76. PubMed
  17. Tervaert, J. W., Stegeman, C. A., and Kallenberg, C. G. Silicon exposure and vasculitis. Curr Opin.Rheumatol 1998;10(1):12-17. PubMed
  18. Steenland, K. and Stayner, L. Silica, asbestos, man-made mineral fibers, and cancer. Cancer Causes Control 1997;8(3):491-503. PubMed
  19. Boqué N, Valls RM, Pedret A, Puiggrós F, Arola L, Solà R. Relative absorption of silicon from different formulations of dietary supplements: a pilot randomized, double-blind, crossover post-prandial study. Sci Rep 2021;11(1):16479. PubMed

See these in context on the Silicon monograph →

Lemon 2 references
  1. Ruggenenti P, Caruso MR, Cortinovis M, et al. Fresh lemon juice supplementation for the prevention of recurrent stones in calcium oxalate nephrolithiasis: A pragmatic, prospective, randomised, open, blinded endpoint (PROBE) trial. EClinicalMedicine 2021;4 PubMed
  2. Umemura K, Katada Y, Nakagawa S, et al. Improved absorption of itraconazole tablet by co-administration with lemon beverages in a lung transplant recipient: A case report. J Infect Chemother 2022;28(8):1203-1207. PubMed

See these in context on the Lemon monograph →

Quercetin 26 references
  1. Shoskes DA, Zeitlin SI, Shahed A, Rajfer J. Quercetin in men with category III chronic prostatitis: A preliminary prospective, double-blind, placebo-controlled trial. Urol 1999;54:960-3. PubMed
  2. Starvic B. Quercetin in our diet: from potent mutagen to probable anticarcinogen. Clin Biochem 1994;27:245-8. PubMed
  3. Ferry DR, Smith A, Malkhandi J, et al. Phase I clinical trial of the flavonoid quercetin: Pharmacokinetics and evidence for in vivo tyrosine kinase inhibition. Clin Cancer Res 1996;2:659-67..
  4. Obach RS. Inhibition of human cytochrome P450 enzymes by constituents of St. John's wort, an herbal preparation used in the treatment of depression. J Pharmacol Exp Ther 2000;294:88-95. DOI
  5. Edwards RL, Lyon T, Litwin SE, et al. Quercetin reduces blood pressure in hypertensive subjects. J Nutr 2007;137:2405-11.
  6. Kim KA, Park PW, Kim HK, et al. Effect of quercetin on the pharmacokinetics of rosiglitazone, a CYP2C8 substrate, in healthy subjects. J Clin Pharmacol 2005;45:941-6. PubMed
  7. DiCenzo R, Frerichs V, Larppanichpoonphol P, et al. Effect of quercetin on the plasma and intracellular concentrations of saquinavir in healthy adults. Pharmacotherapy 2006;26:1255-61. PubMed
  8. Choi JS, Choi BC, Choi KE. Effect of quercetin on the pharmacokinetics of oral cyclosporine. Am J Health Syst Pharm 2004;61:2406-9. PubMed
  9. Choi JS, Jo BW, Kim YC. Enhanced paclitaxel bioavailability after oral administration of paclitaxel or prodrug to rats pretreated with quercetin. Eur J Pharm Biopharm 2004;57:313-8. PubMed
  10. Vaclavikova R, Horsky S, Simek P, Gut I. Paclitaxel metabolism in rat and human liver microsomes is inhibited by phenolic antioxidants. Naunyn Schmiedebergs Arch Pharmacol 2003;368:200-9. PubMed
  11. Di Bari L, Ripoli S, Pradhan S, Salvadori P. Interactions between quercetin and warfarin for albumin binding: A new eye on food/drug interference. Chirality 2010;22:593-6. PubMed
  12. Lamson, D. W. and Brignall, M. S. Antioxidants and cancer, part 3: quercetin. Altern.Med.Rev. 2000;5(3):196-208.
  13. Duan KM, Wang SY, Ouyang W, Mao YM, Yang LJ. Effect of quercetin on CYP3A activity in Chinese healthy participants. J Clin Pharmacol 2012;52(6):940-6. PubMed
  14. Wang SY, Duan KM, Li Y, et al. Effect of quercetin on P-glycoprotein transport ability in Chinese healthy subjects. Eur J Clin Nutr 2013;67(4):390-4. PubMed
  15. Nguyen MA, Staubach P, Wolffram S, Langguth P. Effect of single-dose and short-term administration of quercetin on the pharmacokinetics of talinolol in humans - Implications for the evaluation of transporter-mediated flavonoid-drug interactions. Eur J Pha PubMed
  16. Wu LX, Guo CX, Chen WQ, et al. Inhibition of the organic anion-transporting polypeptide 1B1 by quercetin: an in vitro and in vivo assessment. Br J Clin Pharmacol 2012;73(5):750-7.
  17. Ahrens MJ, Thompson DL. Effect of emulin on blood glucose in type 2 diabetics. J Med Food. 2013;16(3):211-5. PubMed
  18. Larson A, Witman MA, Guo Y, et al. Acute, quercetin-induced reductions in blood pressure in hypertensive individuals are not secondary to lower plasma angiotensin-converting enzyme activity or endothelin-1: nitric oxide. Nutr Res. 2012;32(8):557-64. PubMed
  19. Bedada SK, Neerati P. Evaluation of the effect of quercetin treatment on CYP2C9 enzyme activity of diclofenac in healthy human volunteers. Phytother Res. 2018 Feb;32(2):305-311. doi: 10.1002/ptr.5978. PubMed
  20. Zhao Q, Wei J, Zhang H. Effects of quercetin on the pharmacokinetics of losartan and its metabolite EXP3174 in rats. Xenobiotica 2019;49(5):563-8. PubMed
  21. Bhutani P, Rajanna PK, Paul AT. Impact of quercetin on pharmacokinetics of quetiapine: insights from in-vivo studies in wistar rats. Xenobiotica. 2020:1-7.
  22. Li C, Wang X, Bi Y, et al. Potent Inhibitors of Organic Anion Transporters 1 and 3 From Natural Compounds and Their Protective Effect on Aristolochic Acid Nephropathy. Toxicol Sci. 2020;175(2):279-291. PubMed
  23. Ni Y, Duan Z, Zhou D, et al. Identification of Structural Features for the Inhibition of OAT3-Mediated Uptake of Enalaprilat by Selected Drugs and Flavonoids. Front Pharmacol. 2020;11:802. PubMed
  24. Song YK, Yoon JH, Woo JK, et al. Quercetin is a flavonoid breast cancer resistance protein inhibitor with an impact on the oral pharmacokinetics of sulfasalazine in rats. Pharmaceutics 2020;12(5):397. PubMed
  25. Ahmad E, Jahangir M, Ismail MA, et al. Influence of quercetin pretreatment on pharmacokinetics of warfarin in rats. Curr Drug Saf 2022. PubMed
  26. Nambiar A, Kellogg D 3rd, Justice J, et al. Senolytics dasatinib and quercetin in idiopathic pulmonary fibrosis: results of a phase I, single-blind, single-center, randomized, placebo-controlled pilot trial on feasibility and tolerability. EBioMedicine 20 PubMed

See these in context on the Quercetin monograph →

Stinging Nettle 23 references
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  3. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  4. Schulz V, Hansel R, Tyler VE. Rational Phytotherapy: A Physician's Guide to Herbal Medicine. Terry C. Telger, transl. 3rd ed. Berlin, GER: Springer, 1998.
  5. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  6. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  7. Mittman P. Randomized, double-blind study of freeze-dried Urtica dioica in the treatment of allergic rhinitis. Planta Med 1990;56:44-7.
  8. Vontobel HP, Herzog R, Rutishauser G, Kres H. [Results of a double-blind study on the effectiveness of ERU (extractum radicis Urticae) capsules in conservative treatment of benign prostatic hyperplasia]. (Abstract). Urologe A 1985;24:49-51.
  9. Randall C, Randall H, Dobbs F, et al. Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J R Soc Med 2000;93:305-9. PubMed
  10. Caliskaner Z, Karaayvaz M, Ozturk S. Misuse of a herb: stinging nettle (Urtica urens) induced severe tongue oedema. Complement Ther Med 2004;12:57-8. PubMed
  11. Krzeski, T., Kazon, M., Borkowski, A., Witeska, A., and Kuczera, J. Combined extracts of Urtica dioica and Pygeum africanum in the treatment of benign prostatic hyperplasia: double-blind comparison of two doses. Clin Ther 1993;15(6):1011-1020.
  12. Randall, C., Meethan, K., Randall, H., and Dobbs, F. Nettle sting of Urtica dioica for joint pain--an exploratory study of this complementary therapy. Complement Ther Med 1999;7(3):126-131. PubMed
  13. Tahri, A., Yamani, S., Legssyer, A., Aziz, M., Mekhfi, H., Bnouham, M., and Ziyyat, A. Acute diuretic, natriuretic and hypotensive effects of a continuous perfusion of aqueous extract of Urtica dioica in the rat. J Ethnopharmacol 2000;73(1-2):95-100. PubMed
  14. Sahin, M., Yilmaz, H., Gursoy, A., Demirel, A. N., Tutuncu, N. B., and Guvener, N. D. Gynaecomastia in a man and hyperoestrogenism in a woman due to ingestion of nettle (Urtica dioica). N.Z.Med.J. 2007;120(1265):U2803.
  15. Randall, C., Dickens, A., White, A., Sanders, H., Fox, M., and Campbell, J. Nettle sting for chronic knee pain: a randomised controlled pilot study. Complement Ther.Med. 2008;16(2):66-72. PubMed
  16. Rayburn, K., Fleischbein, E., Song, J., Allen, B., Kundert, M., Leiter, C., and Bush, T. Stinging nettle cream for osteoarthritis. Altern.Ther.Health Med. 2009;15(4):60-61.
  17. Oliver, F., Amon, E. U., Breathnach, A., Francis, D. M., Sarathchandra, P., Black, A. K., and Greaves, M. W. Contact urticaria due to the common stinging nettle (Urtica dioica)-- histological, ultrastructural and pharmacological studies. Clin Exp Dermato PubMed
  18. Kulze, A. and Greaves, M. Contact urticaria caused by stinging nettles. Br.J Dermatol. 1988;119(2):269-270. PubMed
  19. Patten G. Medicinal plant review: Urtica. Aust J Med Herbalism 1993;5(1):5-13.
  20. Maor D, Little M. Skin contact with a stinging tree requiring intensive care unit admission. Contact Dermatitis. 2017 Nov;77(5):335-37. PubMed
  21. Easton L, Vaid S, Nagel AK, Venci JV, Fortuna RJ. Stinging Nettle (Urtica dioica): An Unusual Case of Galactorrhea. Am J Case Rep 2021;22:e933999. PubMed
  22. Niazi B, Ahmed K, Ahmed M, Ali S, Song K, Elias S. Drug-Induced Liver Injury from Herbal Liver Detoxification Tea. Case Rep Gastroenterol 2022;16(3):612-617. PubMed
  23. Nnamani I, Tolu-Akinnawo O, Dufera RR, Akintunde A, Maliakkal B. Tinospora cordifolia (Guduchi/Giloy)-Induced Liver Injury: A Case Review. Cureus 2023;15(5):e39793. PubMed

See these in context on the Stinging Nettle monograph →

Fenugreek 30 references
  1. Madar Z, Thorne R. Dietary fiber. Prog Food Nutr Sci 1987;11:153-74.
  2. Sharma RD, Raghuram TC, Rao NS. Effect of fenugreek seeds on blood glucose and serum lipids in type I diabetes. Eur J Clin Nutr 1990;44:301-6.
  3. Patil SP, Niphadkar PV, Bapat MM. Allergy to fenugreek (Trigonella foenum graecum). Ann Allergy Asthma Immunol 1997;78:297-300. PubMed
  4. Lambert J, Cormier J. Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy 2001;21:509-12. PubMed
  5. Bordia A, Verma SK, Srivastava KC. Effect of ginger (Zingiber officinale Rosc.) and fenugreek (Trigonella foenumgraecum L.) on blood lipids, blood sugar and platelet aggregation in patients with coronary artery disease. Prostaglandins Leukot Essent Fatty PubMed
  6. Yalcin SS, Tekinalp G, Ozalp I. Peculiar odor of traditional food and maple syrup urine disease. Pediatr Int 1999;41:108-9. PubMed
  7. Sewell AC, Mosandl A, Bohles H. False diagnosis of maple syrup urine disease owing to ingestion of herbal tea. N Engl J Med 1999;341:769.. PubMed
  8. Abdo MS, al-Kafawi AA. Experimental studies on the effect of Trigonella foenum-graecum (abstract). Planta Med 1969;17:14-8.
  9. Gupta A, Gupta R, Lal B. Effect of Trigonella foenum-graecum (fenugreek) seeds on glycaemic control and insulin resistance in type 2 diabetes mellitus: a double blind placebo controlled study. J Assoc Physicians India 2001;49:1057-61.
  10. Gabay MP. Galactogogues: medications that induce lactation. J Hum Lact 2002;18:274-9. PubMed
  11. Chevassus H, Gaillard JB, Farret A, et al. A fenugreek seed extract selectively reduces spontaneous fat intake in overweight subjects. Eur J Clin Pharmacol 2010;66(5):449-55. PubMed
  12. Turkyilmaz C, Onal E, Hirfanoglu IM, et al. The effect of galactagogue herbal tea on breast milk production and short-term catch-up of birth weight in the first week of life. J Altern Complement Med 2011;17(2):139-42. PubMed
  13. Swafford S, Berens P. Effect of fenugreek on breast milk volume. Abstract presented at: 5th International Meeting of the Academy of Breastfeeding Medicine; September 11-13,2000, Tucson, Arizona.
  14. Abdel-Barry, J. A., Abdel-Hassan, I. A., Jawad, A. M., and al Hakiem, M. H. Hypoglycaemic effect of aqueous extract of the leaves of Trigonella foenum-graecum in healthy volunteers. East Mediterr.Health J 2000;6(1):83-88. DOI
  15. Parvizpur, A., Ahmadiani, A., and Kamalinejad, M. Probable role of spinal purinoceptors in the analgesic effect of Trigonella foenum (TFG) leaves extract. J Ethnopharmacol 3-8-2006;104(1-2):108-112. PubMed
  16. Mora, A., Herrrera, A., Lopez, C., Dahbi, G., Mamani, R., Pita, J. M., Alonso, M. P., Llovo, J., Bernardez, M. I., Blanco, J. E., Blanco, M., and Blanco, J. Characteristics of the Shiga-toxin-producing enteroaggregative Escherichia coli O104:H4 German ou
  17. Blanco, J. [Stx2a-producing enteroaggregative Escherichia coli O104:H4-ST678. Microbiological diagnostic already, for this and other STEC/VTEC serotypes!]. Enferm.Infecc.Microbiol.Clin. 2012;30(2):84-89.
  18. Beutin, L. and Martin, A. Outbreak of Shiga toxin-producing Escherichia coli (STEC) O104:H4 infection in Germany causes a paradigm shift with regard to human pathogenicity of STEC strains. J Food Prot. 2012;75(2):408-418. PubMed
  19. King LA, Nogareda F, Weill FX, Mariani-Kurkdjian P, Loukiadis E, Gault G, Jourdan-DaSilva N, Bingen E, Macé M, Thevenot D, Ong N, Castor C, Noël H, Van Cauteren D, Charron M, Vaillant V, Aldabe B, Goulet V, Delmas G, Couturier E, Le Strat Y, Combe C, Delm
  20. Reeder C, Legrand A, O'Connor-Von SK. The Effect of Fenugreek on Milk Production and Prolactin Levels in Mothers of Preterm Infants. Clinical Lactation 2013;4(4):159-165. DOI
  21. Al-Jenoobi FI, Ahad A, Mahrous GM, Al-Mohizea AM, AlKharfy KM, Al-Suwayeh SA. Effects of fenugreek, garden cress, and black seed on theophylline pharmacokinetics in beagle dogs. Pharm Biol 2015;53(2):296-300. PubMed
  22. Rao A, Steels E, Inder WJ, Abraham S, Vitetta L. Testofen, a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males in a doubl
  23. Steels E, Rao A, Vitetta L. Physiological aspects of male libido enhanced by standardized Trigonella foenum-graecum extract and mineral formulation. Phytother Res. 2011 Sep;25(9):1294-300.
  24. Gong J, Fang K, Dong H, Wang D, Hu M, Lu F. Effect of fenugreek on hyperglycaemia and hyperlipidemia in diabetes and prediabetes: A meta-analysis. J Ethnopharmacol. 2016 Dec 24;194:260-268. PubMed
  25. Ouzir M, El Bairi K, Amzazi S. Toxicological properties of fenugreek (Trigonella foenum graecum). Food Chem Toxicol. 2016 Oct;96:145-54. PubMed
  26. Khodamoradi K, Khosropanah MH, Ayati Z, et al. The Effects of Fenugreek on Cardiometabolic Risk Factors in Adults: A Systematic Review and Meta-analysis. Complement Ther Med. 2020;52:102416. PubMed
  27. Alkharfy K, Jan B, Alotaibi K, et al. Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model. Curr Drug Metab 2021;22(12):969-977. PubMed
  28. Bin Jardan YA, Ahad A, Raish M, Alam MA, Al-Mohizea AM, Al-Jenoobi FI. Effects of garden cress, fenugreek and black seed on the pharmacodynamics of metoprolol: an herb-drug interaction study in rats with hypertension. Pharm Biol 2021;59(1):1088-1097. PubMed
  29. Al-Mohizea AM, Ahad A, El-Maghraby GM, et al. Effects of Nigella sativa, Lepidium sativum and Trigonella foenum-graecum on sildenafil disposition in beagle dogs. Eur J Drug Metab Pharmacokinet. 2015;40(2):219-24. PubMed
  30. Alkharfy KM, Al-Jenoobi FI, Al-Mohizea AM, et al. Effects of Lepidium sativum, Nigella sativa and Trigonella foenum-graceum on phenytoin pharmacokinetics in beagle dogs. Phytother Res. 2013;27(12):1800-4.

See these in context on the Fenugreek 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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