Interactions on record — worth a quick check against your medications. Based on 3 of 4 ingredients. Check your meds →
Dietary supplement

Quercetin Bioflavonoids Ingredients & Drug Interactions

by NutriCology

Quercetin Bioflavonoids 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 Bioflavonoids 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 Bioflavonoids is a dietary supplement by NutriCology with 4 active ingredients. Its ingredients are commonly taken for varicose veins and chronic venous insufficiency, hemorrhoids, easy bruising and fragile capillaries.Based on those ingredients, 1,169 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Quercetin, Rutin, Lemon Bioflavonoid Complex. 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 Bioflavonoids by NutriCology

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Quercetin Bioflavonoids by NutriCology

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 Sep 10, 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.

This product contains 4 active ingredients: rutin, quercetin, lemon bioflavonoid complex, and citrus fruit extract. Rutin and quercetin are plant-derived compounds (bioflavonoids) with antioxidant properties; they're both flavonoids naturally found in fruits and vegetables.

The lemon bioflavonoid complex and citrus extract round out the bioflavonoid profile from citrus sources. The capsule also holds inactive ingredients—microcrystalline cellulose, hydroxypropyl methylcellulose, and L-leucine—which are fillers and binders that have no active role.

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: Bioflavonoid nutritional supplement.
  • We looked for evidence on: Chronic venous insufficiency (CVI), Hemorrhoids, Varicose veins, Allergic rhinitis (hay fever), Cardiovascular disease (CVD), Hypercholesterolemia — and 4 related terms.
  • The closest evidence on file: Rutin is rated "Insufficient Reliable Evidence To Rate" for Hemorrhoids (Natural Medicines).
  • Also on file: Rutin is rated "Insufficient Reliable Evidence To Rate" for Varicose veins.
  • Also on file: Quercetin is rated "Insufficient Reliable Evidence To Rate" for Allergic rhinitis (hay fever), Cardiovascular disease (CVD), Chronic venous insufficiency (CVI), Upper respiratory tract infection (URTI), and more.

For the ingredients we have effectiveness data on, the evidence is sparse. Rutin has insufficient evidence to rate for aging skin, autism spectrum disorder, inflammatory bowel disease, diabetes, exercise-induced respiratory infections, and hemorrhoids.

Quercetin shows possibly ineffective for athletic performance and insufficient evidence for age-related cognitive decline, hay fever, Alzheimer disease, asthma, and atherosclerosis. Lemon bioflavonoid complex likewise lacks reliable evidence for hay fever, anxiety, respiratory tract infections, high blood pressure, and kidney stones.

The facts don't establish that this product works for any specific condition.

The evidence, ingredient by ingredient Rutin Quercetin Lemon

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Rutin and quercetin are generally well tolerated in food and short-term supplement use, but long-term safety data are limited. Rutin may cause headache, flushing, or rashes in some people.

Quercetin may cause headache and tingling of the hands or feet. Lemon bioflavonoid complex is well tolerated in food amounts, but concentrated supplements have not been well studied; fresh lemon juice at high doses (60 mL twice daily) caused gastrointestinal disturbances—heartburn and stomach pain—in a significant portion of trial participants.

For pregnancy: rutin is rated likely safe, but quercetin and lemon bioflavonoid complex lack enough safety data—the facts advise against supplement doses during pregnancy. For breastfeeding: rutin data advises against supplement doses due to unknown safety, and quercetin and lemon complex also lack adequate safety information.

Talk with your doctor or pharmacist about whether this product is right for you during pregnancy or while breastfeeding.

Side effects, ingredient by ingredient Rutin Quercetin Lemon

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 3 matched ingredients can interact with medications — Rutin, Quercetin, Lemon.
  • 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: 1,170 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 this product, double-check with your doctor or pharmacist if you're on any blood thinners (especially warfarin), blood pressure medications like losartan, cholesterol drugs (particularly pravastatin or drugs transported by OATP), antidiabetes medications, cyclosporine, sulfasalazine or mitoxantrone, quinolone antibiotics, or the antifungal itraconazole. The interactions documented here range from moderate to minor in severity and may affect how your medications work or increase side effects.

Check your own medication Run your meds through the checker above

The bottom line

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

This quercetin and rutin supplement may be worth considering if you're looking for a general bioflavonoid source, but the evidence for specific health claims is not established. If you take blood thinners, blood pressure or cholesterol drugs, antidiabetes medications, immunosuppressants, or antibiotics, you need to check with your own doctor or pharmacist before starting it—the interactions are real and potentially serious.

Pregnant or breastfeeding individuals should also talk it over with their healthcare provider first.

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

Assessment coverage: 3 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 25, 2020.

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 Bioflavonoids, straight from the product label.

Brand NutriCology
Barcode (UPC) 713947500501
Net contents 100 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Sep 25, 2020
DSLD ID 234791
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years)
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 Bioflavonoids by NutriCology, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
50
UPC/BARCODE
713947500501
IngredientAmount% DV
Rutin100 mg--
Quercetin100 mg--
Lemon Bioflavonoid Complex800 mg--
Citrus (fruit) extract100 mg--

Other ingredients: Hydroxypropyl Methylcellulose, Microcrystalline Cellulose, L-Leucine

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.
Formula

Provides Quercetin extracted from a non-citrus plant source, and other bioflavonoids extracted from lemon, for a classical offering from the bioflavonoid group of nutritional supplements.

Suggested/Recommended/Usage/Directions

Suggested Use As a dietary supplement, 1 or 2 capsules one to three times daily with meals, or as directed by a healthcare practitioner.

Formulation

Variations in product color may occur.

Hypoallergenic

Storage

Keep in a cool, dry place, tightly capped.

Precautions

Warning: Consuming this product can expose you to lead which is known to the State of California to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov/food

General Statements

NutriCology Innovative Nutrition

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

Quercetin Bioflavonoids by NutriCology label

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

Quercetin Bioflavonoids 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 Bioflavonoids by NutriCology

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container50 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.

Rutin

Interacts with
86 drugs
100 mg per serving

Rutin is a plant flavonoid (often taken from buckwheat or citrus) that people use mainly for blood vessel and circulation problems like varicose veins...

Rutin monograph & interactions

Quercetin

Interacts with
1,169 drugs
100 mg per serving

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

Lemon Bioflavonoid Complex

Interacts with
1 drug
800 mg per serving

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...

Lemon Bioflavonoid Complex monograph & interactions

Citrus (fruit) extract

100 mg per serving Form: Hesperidin

Other (inactive) ingredients: Hydroxypropyl Methylcellulose, Microcrystalline Cellulose, L-Leucine. These complete the product’s ingredient list but are not active constituents.

Interaction report

Quercetin Bioflavonoids by NutriCology Drug Interactions

Want to check YOUR meds against Quercetin Bioflavonoids?

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
1,169Drugs
1,169 Moderate

Ingredients driving the most interactions

Quercetin 1,169
Rutin 86
Lemon Bioflavonoid Complex 1

Individual Drug Interactions

The ingredients in Quercetin Bioflavonoids interact with 1,169 drugs. Click any drug to see the details.

3 of the 4 ingredients in Quercetin Bioflavonoids interact with drugs. Each result below shows which ingredient is responsible. Quercetin Rutin Lemon Bioflavonoid Complex

Each ingredient & the kinds of drugs it affects

For each ingredient in Quercetin Bioflavonoids 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

Rutin1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking rutin with antidiabetes drugs might increase the risk of hypoglycemia.
Animal research suggests that rutin has hypoglycemic effects.

Likelihood Possible Evidence D
Rutin full monograph & interactions

Lemon Bioflavonoid Complex1 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 Bioflavonoid Complex full monograph & interactions
The maker

Brand information

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

NutriCology

See all NutriCology products
Name
NutriCology
City
South Salt Lake
State
UT
ZipCode
84115
Phone Number
800.545.9960
Web Address
www.allergyresearchgroup.com
Pharmacist Counseling Corner

Quercetin Bioflavonoids by NutriCology: Common Questions

Does Quercetin Bioflavonoids by NutriCology interact with any medications?
Yes. Based on its ingredients, Quercetin Bioflavonoids has a known interaction with 1,169 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Quercetin Bioflavonoids 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.
What is rutin and what does it do?
Rutin is a bioflavonoid—a plant compound with antioxidant properties—found naturally in fruits, berries, and vegetables. It's one of the active ingredients in this supplement. The evidence for specific health benefits in supplement form is not yet established for the conditions we have data on.
Can I take this while pregnant or breastfeeding?
Rutin is rated likely safe in pregnancy, but quercetin and lemon bioflavonoid complex don't have enough safety data—the facts advise against supplement doses for both. While breastfeeding, there isn't enough information on any of these ingredients. Talk with your doctor or pharmacist to decide what's right for you.
What side effects might I experience?
Rutin and quercetin may cause headache in some people. Quercetin may also cause tingling in your hands or feet. Lemon bioflavonoid complex at high doses can trigger heartburn and stomach discomfort—about one in five people in a trial taking high-dose lemon juice reported heartburn. These are typically mild, but let your pharmacist know if they persist.
Is this product well tolerated in the long term?
Rutin and quercetin are generally well tolerated in food and short-term supplement use, but high-quality long-term safety data are limited. Lemon bioflavonoid complex in food amounts is safe, but concentrated supplement forms haven't been well studied over time.
Does this help with diabetes or blood sugar?
Animal research suggests rutin may lower blood sugar, which is why there's a documented interaction with antidiabetes drugs. However, there's insufficient reliable evidence that rutin actually works for diabetes in people, so we can't say whether this supplement helps that condition.
I take warfarin for blood clots—is this safe for me?
No—quercetin in this product may increase warfarin levels in your blood and raise your bleeding risk. Talk with your doctor or pharmacist before taking this supplement if you're on any blood thinner.

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.

Quercetin Bioflavonoids label
Go deeper

The Full Monographs Behind Quercetin Bioflavonoids’s Ingredients

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

Herb & supplement monograph

Rutin

Interacts with 86 drugs

Rutin is a plant flavonoid (often taken from buckwheat or citrus) that people use mainly for blood vessel and circulation problems like varicose veins and hemorrhoids. The evidence is limite...

Read the full Rutin monograph → 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

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 →
Sources

Sources & How We Checked

Quercetin Bioflavonoids'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 30 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.

Rutin 2 references
  1. Mehta DK (Ex Ed). British National Formulary, Number 37. British Medical Association and Royal Pharmaceutical Society of Great Britain: London, England, March 1999.
  2. Sun C, Wang L, Sun J, Wang Z, Tang Z. Hypoglycemic and hypolipidemic effects of rutin on hyperglycemic rats. J Tradit Chin Med. 2020;40(4):640-645.

See these in context on the Rutin 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
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  12. Lamson, D. W. and Brignall, M. S. Antioxidants and cancer, part 3: quercetin. Altern.Med.Rev. 2000;5(3):196-208.
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  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
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See these in context on the Quercetin 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 →

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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