Quercetin Dihydrate Ingredients & Drug Interactions
What is this page for?
First and foremost: checking Quercetin Dihydrate 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
Quercetin Dihydrate is a dietary supplement by BulkSupplements.com with 1 active ingredient. Its ingredients are commonly taken for seasonal allergies, antioxidant support, heart and blood pressure health.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 Dihydrate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Quercetin Dihydrate by BulkSupplements.com
Ask about any prescription or over-the-counter medication and we check it for interactions with Quercetin Dihydrate by BulkSupplements.com — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Quercetin Dihydrate by BulkSupplements.com
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.
What’s inside
Full disclosure
This product contains one active ingredient: Quercetin Dihydrate, a plant-derived compound. There are no inactive ingredients listed.
Does it work?
Couldn't assess
Quercetin Dihydrate's effectiveness is not well established for most uses. The evidence rates quercetin as possibly ineffective for athletic performance.
For age-related cognitive decline, hay fever (allergic rhinitis), Alzheimer disease, asthma, and hardening of the arteries (atherosclerosis), there isn't enough reliable evidence in our data to rate it one way or the other.
How safe is it?
Well-documented data
Quercetin is generally well tolerated in food amounts and typical supplement doses, but high doses and long-term safety haven't been well studied. When taken by mouth, it may cause headache or tingling in your hands and feet.
The safety data advises against taking supplemental doses during pregnancy or while breastfeeding because there isn't enough information to know whether it's safe in those situations.
Meds to double-check
Moderate interaction found
Before taking Quercetin Dihydrate, check with your doctor or pharmacist if you take blood thinners like warfarin (Coumadin), blood pressure medications like losartan (Cozaar), cholesterol drugs like pravastatin (Pravachol) or other OATP substrates, quinolone antibiotics, cyclosporine (Neoral, Sandimmune), sulfasalazine (Azulfidine), or mitoxantrone (a cancer medication). All carry moderate-severity interaction risks with this product.
The bottom line
Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
Quercetin Dihydrate may appeal to someone interested in general wellness, but it carries real interaction risks with blood thinners, blood pressure drugs, cholesterol medications, antibiotics, and several other prescription classes. If you take any regular medications—especially warfarin or other blood thinners—talk with your doctor or pharmacist before adding this product.
The same goes if you're pregnant, breastfeeding, or taking high doses long-term.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Apr 23, 2024.
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
General information
Key facts about Quercetin Dihydrate, straight from the product label.
| Brand | BulkSupplements.com |
|---|---|
| Barcode (UPC) | X000IXQ40F |
| Net contents | 250 Gram(s); 8.8 Ounce(s) |
| Market status | On market |
| Date entered into DSLD | Apr 23, 2024 |
| DSLD ID | 311816 |
| Product type | Non-nutrient/non-botanical |
| Supplement form | Powder |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 Dihydrate by BulkSupplements.com, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Quercetin Dihydrate | 500 mg | -- |
Tap any ingredient to jump to its full detail below.
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.
Brand IP Statement(s)
Bulksupplements.com Clean & pure bulk supplements
Formulation
Free of: Sugar, soy, dairy, yeast, gluten, additives
Immune system vitamins Clear skin supplement
Vegan supplement
Suggested/Recommended/Usage/Directions
Suggested Use: As a dietary supplement, take 500 mg (about 1/5 tsp) once or twice daily with food, or as directed by a physician.
Precautions
Do not exceed 1 gram daily.
Always consult a physician before taking any dietary supplement.
Keep out of reach of children.
General Statements
Use an accurate milligram scale.
New
Storage
Contents are sold by weight, not volume. Settling may occur. Store in a dry, cool, dark place.
FDA Disclaimer Statement
Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.
Formula
Quinine supplement
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Quercetin Dihydrate by BulkSupplements.com label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Quercetin Dihydrate by BulkSupplements.com
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size500 mg Dosage formPowder Servings per container500 Amounts shown are per serving.
Quercetin Dihydrate
Interacts with1,169 drugs
Quercetin is a plant flavonoid with antioxidant and anti-inflammatory properties found in many common foods and sold as a supplement. While early rese...
Quercetin Dihydrate monograph & interactionsQuercetin Dihydrate by BulkSupplements.com Drug Interactions
HelloPharmacist Interaction Report
Quercetin Dihydrate by BulkSupplements.com does interact with medications.
The main concern is through its effects on how your body processes and absorbs certain drugs. Altogether, these interactions span 1,170 individual medications.
Read the full breakdown — every affected drug type, severity by severity
The most serious documented interaction is with blood thinners like warfarin (Coumadin). Quercetin may increase warfarin levels in your blood and raise your bleeding risk.
Animal and lab studies show that quercetin and warfarin compete for the same binding site in blood proteins, and quercetin appears to win that competition, displacing warfarin and raising its levels.
Other moderate interactions involve blood pressure drugs (losartan), cholesterol medications (pravastatin and other OATP substrates), antibiotics (quinolones), immune-suppressing drugs (cyclosporine), anti-inflammatory medications (sulfasalazine), and certain cancer drugs (mitoxantrone). In each case, quercetin may increase drug levels or effects in your blood.
The mechanism varies—some involve blocking the proteins that transport drugs into cells, others involve slowing how your liver breaks down the medication.
If you take any prescription medications, run them through the interaction checker on this page before starting quercetin.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Quercetin Dihydrate?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Quercetin Dihydrate interact with 1,169 drugs. Click any drug to see the details.
1 of the 1 ingredient in Quercetin Dihydrate interact with drugs. Each result below shows which ingredient is responsible. Quercetin Dihydrate
AlfentanilAlfenta
How Alfentanil interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Alfentanil interactionAlfuzosinUroxatral
How Alfuzosin interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Alfuzosin interactionAliskirenTekturna
How Aliskiren interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates, Antihypertensive Drugs Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Aliskiren interactionAlmotriptanAlmogran, Axert
How Almotriptan interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Almotriptan interactionAlogliptinNesina
How Alogliptin interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntidiabetes Drugs, Cytochrome P450 2c8 (cyp2c8) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use of quercetin and antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Quercetin Dihydrate + Alogliptin interactionAlogliptin, MetforminKazano
How Alogliptin, Metformin interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, concomitant use of quercetin and antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Quercetin Dihydrate + Alogliptin, Metformin interactionAlogliptin, PioglitazoneOseni
How Alogliptin, Pioglitazone interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntidiabetes Drugs, Cytochrome P450 2c8 (cyp2c8) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use of quercetin and antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Quercetin Dihydrate + Alogliptin, Pioglitazone interactionAlpelisibPiqray
How Alpelisib interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Alpelisib interactionAlprazolamNiravam, Xanax
How Alprazolam interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Alprazolam interactionAluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2
How Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateOrganic Anion Transporter 3 (oat3) Substrates, Organic Anion Transporter 1 (oat1) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use might increase the effects and adverse effects of OAT3 substrates.
Read the full Quercetin Dihydrate + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionAluminum Hydroxide, Aspirin, Magnesium HydroxideAscriptin
How Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateOrganic Anion Transporter 3 (oat3) Substrates, Organic Anion Transporter 1 (oat1) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might increase the effects and adverse effects of OAT3 substrates.
Read the full Quercetin Dihydrate + Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interactionAlvimopanEntereg
How Alvimopan interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateP-glycoprotein Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of P-glycoprotein substrates.
Read the full Quercetin Dihydrate + Alvimopan interactionAmbrisentanLetairis, Volibris
How Ambrisentan interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateP-glycoprotein Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of P-glycoprotein substrates.
Read the full Quercetin Dihydrate + Ambrisentan interactionAmilorideAmilamont, Midamor
How Amiloride interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Amiloride interactionAmiloride, HydrochlorothiazideAmil-Co, Amilzide, Moduret 25, Moduretic
How Amiloride, Hydrochlorothiazide interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs, Organic Anion Transporter 3 (oat3) Substrates +1 Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Amiloride, Hydrochlorothiazide interactionAmiodaroneCordarone, Pacerone
How Amiodarone interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2c8 (cyp2c8) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Amiodarone interactionAmitriptylineElavil
How Amitriptyline interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 2c9 (cyp2c9) Substrates, Cytochrome P450 2d6 (cyp2d6) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use might increase the levels and adverse effects of CYP2C9 substrates.
Read the full Quercetin Dihydrate + Amitriptyline interactionAmitriptyline, ChlordiazepoxideLimbitrol DS
How Amitriptyline, Chlordiazepoxide interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2c9 (cyp2c9) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Amitriptyline, Chlordiazepoxide interactionAmitriptyline, PerphenazineEtrafon, Etrafon-A, Etrafon-Forte, Triavil
How Amitriptyline, Perphenazine interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 2d6 (cyp2d6) Substrates, Cytochrome P450 2c9 (cyp2c9) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use might increase the levels and adverse effects of CYP2D6 substrates.
Read the full Quercetin Dihydrate + Amitriptyline, Perphenazine interactionAmlodipineNorliqva
How Amlodipine interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Amlodipine interactionAmlodipine BenzoateKaterzia
How Amlodipine Benzoate interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates, Antihypertensive Drugs Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Amlodipine Benzoate interactionAmlodipine BesilateIstin
How Amlodipine Besilate interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Amlodipine Besilate interactionAmlodipine BesylateNorvasc
How Amlodipine Besylate interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Amlodipine Besylate interactionAmlodipine Besylate, BenazeprilLotrel
How Amlodipine Besylate, Benazepril interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 3a4 (cyp3a4) Substrates, Antihypertensive Drugs Moderate
Interaction Summary
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
Read the full Quercetin Dihydrate + Amlodipine Besylate, Benazepril interactionAmlodipine, CelecoxibConsensi
How Amlodipine, Celecoxib interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs, Organic Anion Transporter 3 (oat3) Substrates +3 Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Amlodipine, Celecoxib interactionAmmonium ChlorideAmmonium Chloride
How Ammonium Chloride interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateAntihypertensive Drugs Moderate
Interaction Summary
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full Quercetin Dihydrate + Ammonium Chloride interactionAmoxicillin, Omeprazole Magnesium, RifabutinTalicia
How Amoxicillin, Omeprazole Magnesium, Rifabutin interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 2c9 (cyp2c9) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might increase the levels and adverse effects of CYP2C9 substrates.
Read the full Quercetin Dihydrate + Amoxicillin, Omeprazole Magnesium, Rifabutin interactionAmphetamineAdensys XR-ODT, Adzenys ER, Dyanavel XR, Mydayis
How Amphetamine interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 2d6 (cyp2d6) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might increase the levels and adverse effects of CYP2D6 substrates.
Read the full Quercetin Dihydrate + Amphetamine interactionAmphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine SulfateAdderall, Adderall XR
How Amphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 2d6 (cyp2d6) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might increase the levels and adverse effects of CYP2D6 substrates.
Read the full Quercetin Dihydrate + Amphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate interactionAmphetamine SulfateBenzedrine, Evekeo ODT
How Amphetamine Sulfate interacts with Quercetin Dihydrate — through 1 ingredient. Tap an ingredient for the detail:
Quercetin DihydrateCytochrome P450 2d6 (cyp2d6) Substrates Moderate
Interaction Summary
Theoretically, concomitant use might increase the levels and adverse effects of CYP2D6 substrates.
Read the full Quercetin Dihydrate + Amphetamine Sulfate interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Quercetin Dihydrate with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Quercetin Dihydrate
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.
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.
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.
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.
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.
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.
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.
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.
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.
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%.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Brand information
Manufacturer and brand details for Quercetin Dihydrate, from the product label.
BulkSupplements.com
See all BulkSupplements.com products- Name
- BulkSupplements.com
- Street Address
- 7511 Eastgate Rd
- City
- Henderson
- State
- NV
- ZipCode
- 89011
- Web Address
- bulksupplements.com
Quercetin Dihydrate by BulkSupplements.com: Common Questions
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The Full Monographs Behind Quercetin Dihydrate’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Quercetin Dihydrate'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 26 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.
Quercetin 26 references
- 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
- Starvic B. Quercetin in our diet: from potent mutagen to probable anticarcinogen. Clin Biochem 1994;27:245-8. PubMed
- 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..
- 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
- Edwards RL, Lyon T, Litwin SE, et al. Quercetin reduces blood pressure in hypertensive subjects. J Nutr 2007;137:2405-11.
- 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
- 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
- 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
- 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
- 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
- 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
- Lamson, D. W. and Brignall, M. S. Antioxidants and cancer, part 3: quercetin. Altern.Med.Rev. 2000;5(3):196-208.
- 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
- 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
- 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
- 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.
- Ahrens MJ, Thompson DL. Effect of emulin on blood glucose in type 2 diabetics. J Med Food. 2013;16(3):211-5. PubMed
- 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
- 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
- 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
- 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.
- 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
- 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
- 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
- Ahmad E, Jahangir M, Ismail MA, et al. Influence of quercetin pretreatment on pharmacokinetics of warfarin in rats. Curr Drug Saf 2022. PubMed
- 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
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