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Dietary supplement

Quercetin with Zinc Ingredients & Drug Interactions

by aSquared Nutrition

Quercetin with Zinc 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 with Zinc 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 with Zinc is a dietary supplement by aSquared Nutrition with 3 active ingredients. Its ingredients are commonly taken for zinc deficiency, immune support, cold symptoms.Based on those ingredients, 1,261 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Quercetin Dihydrate powder, Black Elderberry, Zinc. 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 with Zinc by aSquared Nutrition

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

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HelloPharmacist Scorecard of Quercetin with Zinc by aSquared Nutrition

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 3, 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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This supplement contains 3 active ingredients: zinc (which supports immune function and wound healing), black elderberry (a traditional immune support ingredient), and quercetin dihydrate powder (a plant compound found in foods). The capsule also contains vegetable cellulose and rice flour as inactive ingredients.

Does it work?

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

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

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Zinc deficiency — rated "Effective" (Zinc) (Natural Medicines).
  • On file: Wilson disease — rated "Likely Effective" (Zinc) (Natural Medicines).
  • On file: Acne — rated "Possibly Effective" (Zinc) (Natural Medicines).
  • On file: Acrodermatitis enteropathica — rated "Possibly Effective" (Zinc) (Natural Medicines).
  • On file: Age-related macular degeneration (AMD) — rated "Possibly Effective" (Zinc) (Natural Medicines).

Zinc is effective for zinc deficiency and likely effective for Wilson disease (a copper-storage disorder). It's possibly effective for acne, a rare skin condition called acrodermatitis enteropathica, age-related macular degeneration, and diabetes.

Black elderberry and quercetin don't have sufficient reliable evidence to rate their effectiveness for the conditions studied in our data, including cold, flu, hay fever, heart disease, fatigue, lung health, memory, or athletic performance.

The evidence, ingredient by ingredient Zinc Elderberry Quercetin

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.

Zinc is generally well tolerated in recommended doses (below 40 mg daily for adults), though higher amounts can cause nausea, diarrhea, metallic taste, and abdominal cramps—effects that are dose-related. Long-term high-dose zinc may raise the risk of copper deficiency.

Black elderberry made from ripe, cooked berries is generally well tolerated, but raw or unripe berries and other plant parts contain toxins that cause severe nausea, vomiting, and diarrhea; cooking eliminates this risk. Quercetin is generally well tolerated in food and typical supplement amounts, though high doses and long-term safety are not well studied.

The safety data advises against supplemental elderberry and quercetin during pregnancy and breastfeeding due to insufficient information.

Side effects, ingredient by ingredient Zinc Elderberry Quercetin

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 — Quercetin, Elderberry, Zinc.
  • 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: 1,262 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.

Double-check this product before taking it if you use antibiotics (quinolones, tetracyclines, or cephalexin), blood thinners like warfarin, cholesterol drugs, blood-pressure medications, HIV drugs, immune-suppressing medications, or chemotherapy agents. All of these interactions are moderate severity.

If you take any of these drug types, confirm with your doctor or pharmacist that the timing and dosing work for you.

Check your own medication Run your meds through the checker above

The bottom line

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

This supplement may be worth considering if you're looking to support zinc levels or general immune health, but it carries real interaction risks with antibiotics, blood thinners, HIV and cancer medications, and several other drug classes. Before you start it, sit down with your doctor or pharmacist and run through your current medications—especially if you take any of those categories.

If you're pregnant or breastfeeding, talk with your provider first.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 11, 2022.

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

At a glance

General information

Key facts about Quercetin with Zinc, straight from the product label.

Brand aSquared Nutrition
Barcode (UPC) X002MDU3OH
Net contents 120 Capsule(s)
Market status On market
Date entered into DSLD Apr 11, 2022
DSLD ID 263994
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Quercetin with Zinc by aSquared Nutrition, 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 Vegetable Capsule(s)
Maximum serving Sizes:
2 Vegetable Capsule(s)
Servings per container
60
UPC/BARCODE
X002MDU3OH
IngredientAmount% DV
Zinc30 mg273%
Black Elderberry200 mg--
Quercetin Dihydrate powder1000 mg--

Other ingredients: Vegetable Cellulose, Rice Flour

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Suggested Use: For adults, take two (2) capsules daily, preferably with a meal. Consult your doctor before use; take periodic breaks from use.

Precautions

Caution: Do not exceed the recommended dose.

Not intended for pregnant or nursing mothers.

Not intended for children under 18 years of age.

If you are taking any medications, have a known medical condition, or are planning a medical procedure, consult your doctor before use.

Avoid this product if you have or have had kidney stones. Discontinue use and consult your doctor if any adverse reactions occur.

Keep out of reach of children.

Do not use if safety seal is damaged or missing.

Seals/Symbols

GMP Good Manufacturing Practice Quality Assured

USA Formulated

General Statements

Please recycle.

Storage

Store in a cool, dry place.

FDA Disclaimer Statement

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

Formulation

Vegan friendly

Made with natural ingredients Max strength flavonoid Supports healthy immunity Helps support heart health Has antioxidant properties

No preservatives

FDA Statement of Identity

Dietary Supplement

Formula

aSquared Nutrition is proud to offer a proprietary Quercetin supplement that is enhanced with Zinc and Black Elderberry. Quercetin is a type of flavonoid that is naturally found in berries, broccoli and leafy greens. Quercetin contains antioxidant properties, and helps support immune & skin health.

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

See for yourself

Quercetin with Zinc by aSquared Nutrition label

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

Quercetin with Zinc 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 with Zinc by aSquared Nutrition

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Vegetable Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

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

Zinc

Interacts with
67 drugs
30 mg per serving Form: Zinc Citrate, Zinc Gluconate

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but suppleme...

Zinc monograph & interactions

Black Elderberry

Interacts with
121 drugs
200 mg per serving

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu sym...

Black Elderberry monograph & interactions

Quercetin Dihydrate powder

Interacts with
1,169 drugs
1000 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 Dihydrate powder monograph & interactions

Other (inactive) ingredients: Vegetable Cellulose, Rice Flour. These complete the product’s ingredient list but are not active constituents.

Interaction report

Quercetin with Zinc by aSquared Nutrition Drug Interactions

Want to check YOUR meds against Quercetin with Zinc?

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
1,261Drugs
1,261 Moderate

Ingredients driving the most interactions

Quercetin Dihydrate powder 1,169
Black Elderberry 121
Zinc 67

Individual Drug Interactions

The ingredients in Quercetin with Zinc interact with 1,261 drugs. Click any drug to see the details.

3 of the 3 ingredients in Quercetin with Zinc interact with drugs. Each result below shows which ingredient is responsible. Quercetin Dihydrate powder Black Elderberry Zinc

Each ingredient & the kinds of drugs it affects

For each ingredient in Quercetin with Zinc 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.

Quercetin Dihydrate powder21 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 Dihydrate powder full monograph & interactions

Black Elderberry2 drug types · 121 drugs

Immunosuppressants

Theoretically, elderberry might interfere with immunosuppressant therapy due to its immunostimulant activity.
Elderberry has immunostimulant activity, increasing the production of cytokines, including interleukin and tumor necrosis factor.

Likelihood Possible Evidence B
Pazopanib (Votrient)

Theoretically, elderberry might interact with pazopanib, potentially increasing the risk of adverse effects.
In one case, a 65-year-old patient taking pazopanib for 4 weeks for soft-tissue sarcoma developed severe nausea, loose stools, and elevated alanine transaminase and aspartate transaminase levels and was diagnosed with grade 3 liver injury. The patient reported taking elderberry supplements for 2 years, dose unspecified, and was also taking a multivitamin and a calcium supplement. The patient's symptoms and liver enzyme levels improved upon discontinuation of pazopanib and all supplements. Pazopanib treatment was re-initiated, at a lower dose, with no further evidence of liver injury. It was unclear in this case report if the elderberry supplements were derived from the berry, the flower, or the combination.

Likelihood Possible Evidence D
Black Elderberry full monograph & interactions

Zinc10 drug types · 67 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Theoretically, zinc might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide should be taken at least 2 hours before or 6 hours after zinc containing products.

Likelihood Probable Evidence D
Cephalexin (Keflex)

Zinc might decrease cephalexin levels by chelating with cephalexin in the gut and preventing its absorption.
A pharmacokinetic study shows that zinc sulfate 250 mg taken concomitantly with cephalexin 500 mg decreases peak levels of cephalexin by 31% and reduces the exposure to cephalexin by 27%. Also, taking zinc sulfate 3 hours before cephalexin decreases peak levels of cephalexin by 11% and reduces the exposure to cephalexin by 18%. By decreasing cephalexin levels, zinc might increase the risk of treatment failure. This effect does not occur when zinc is taken 3 hours after the cephalexin dose. To avoid an interaction, advise patients take zinc sulfate 3 hours after taking cephalexin.

Likelihood Probable Evidence B
Cisplatin (Platinol-Aq)

Theoretically, zinc might interfere with the therapeutic effects of cisplatin.
Animal research suggests that zinc stimulates tumor cell production of the protein metallothionein, which binds and inactivates cisplatin. It is not known whether zinc supplements or high dietary zinc intake can cause clinically significant interference with cisplatin therapy. Cisplatin might also increase zinc excretion.

Likelihood Possible Evidence D
Integrase Inhibitors

Theoretically, taking zinc along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Zinc is a divalent cation. Pharmacokinetic studies have shown that other divalent cations such as calcium and iron can decrease blood levels of the integrase inhibitor dolutegravir through chelation.

Likelihood Possible Evidence D
Penicillamine (Cuprimine, Depen)

Zinc might reduce the levels and clinical effects of penicillamine.
By forming an insoluble complex with penicillamine, zinc interferes with penicillamine absorption and activity. Zinc supplements reduce the efficacy of low-dose penicillamine (0.5-1 gram/day), but do not seem to affect higher doses (1-2.75 gram/day), provided dosing times are separated. Advise patients to take zinc and penicillamine at least 2 hours apart.

Likelihood Probable Evidence B
Quinolone Antibiotics

Zinc can decrease the levels and clinical effects of quinolones antibiotics.
Quinolones form complexes with zinc in the gastrointestinal tract, reducing absorption of both the quinolone and zinc if taken at the same time. Advise patients to take these drugs at least 2 hours before, or 4-6 hours after, zinc supplements.

Likelihood Probable Evidence B
Ritonavir (Norvir)

Zinc modestly reduces levels of ritonavir.
Clinical research shows that zinc might reduce serum ritonavir levels by chelating with ritonavir in the gut and preventing its absorption. In patients with HIV, ritonavir is taken with atazanavir to prevent the metabolism and increase the effects of atazanavir. A pharmacokinetic study shows that, in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate (Solvazinc tablets) 125 mg as a single dose or as multiple daily doses for 2 weeks reduces plasma levels of ritonavir by about 16%. However, atazanavir levels still remains high enough to prevent HIV virus replication. Therefore, the decrease in ritonavir levels is not likely to be clinically significant.

Likelihood Probable Evidence B
Tetracycline Antibiotics

Zinc might reduce levels of tetracycline antibiotics.
Tetracyclines form complexes with zinc in the gastrointestinal tract, which can reduce absorption of both the tetracycline and zinc when taken at the same time. Taking zinc sulfate 200 mg with tetracycline reduces absorption of the antibiotic by 30% to 40%. Demeclocycline and minocycline cause a similar interaction. However, doxycycline does not seem to interact significantly with zinc. Advise patients to take tetracyclines at least 2 hours before, or 4-6 hours after, zinc supplements to avoid any interactions.

Likelihood Probable Evidence B
Amiloride (Midamor)

Amiloride can modestly reduce zinc excretion and increase zinc levels.
Clinical research shows that amiloride can reduce urinary zinc excretion, especially at doses of 10 mg per day or more. This zinc-sparing effect can help to counteract zinc losses caused by thiazide diuretics, but it is unlikely to cause zinc toxicity at usual amiloride doses. The other potassium-sparing diuretics, spironolactone (Aldactone) and triamterene (Dyrenium), do not seem to have a zinc-sparing effect.

Likelihood Probable Evidence B
Atazanavir (Reyataz)

Zinc modestly reduces levels of atazanavir, although this effect does not seem to be clinically significant.
Clinical research shows that zinc might decrease serum atazanavir levels by chelating with atazanavir in the gut and preventing its absorption. Although a single dose of zinc sulfate (Solvazinc tablets) 125 mg orally does not affect atazanavir concentrations in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate 125 mg daily for 2 weeks reduces plasma levels of atazanavir by about 22% in these patients. However, despite this decrease, atazanavir levels still remain at high enough concentrations for the prevention of HIV virus replication.

Likelihood Probable Evidence B
Zinc full monograph & interactions
The maker

Brand information

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

aSquared Nutrition

See all aSquared Nutrition products
Name
aSquared Brands LLC
Street Address
382 NE 191st Street, #98406
City
Miami
State
FL
ZipCode
33179
Phone Number
Office: 1-800-557-4120
Pharmacist Counseling Corner

Quercetin with Zinc by aSquared Nutrition: Common Questions

Does Quercetin with Zinc by aSquared Nutrition interact with any medications?
Yes. Based on its ingredients, Quercetin with Zinc has a known interaction with 1,261 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Quercetin with Zinc contains 3 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 does zinc do in this supplement?
Zinc supports your immune system and wound healing. It's an effective treatment for zinc deficiency and likely effective for Wilson disease. It may also help with acne, age-related eye health, and diabetes, though the evidence is still building.
Can I take this with my antibiotic?
Not without spacing them apart. Zinc reduces how much antibiotic your body absorbs—cutting some types by nearly 40%. If you take a quinolone, tetracycline, or cephalexin antibiotic, take it at least 2–4 hours before or after this supplement. Check with your pharmacist for your specific antibiotic.
Is this safe if I'm pregnant?
The safety data advises against taking supplemental elderberry and quercetin during pregnancy due to not enough information. Zinc's pregnancy rating is mixed in our data. Talk with your doctor or pharmacist before starting this product.
What side effects might I notice?
Zinc can cause nausea, diarrhea, a metallic taste, or stomach cramps—especially at higher doses. Quercetin may cause headache or tingling in your fingers and toes. Black elderberry, if made from ripe cooked berries, is generally well tolerated.
Does this supplement have any fillers?
It contains vegetable cellulose and rice flour as inactive ingredients, which are common binders and flow agents in capsules.
Can I take this with my blood thinner or cholesterol medication?
Not without checking first. Quercetin can theoretically increase the effects of warfarin (raising bleeding risk) and cholesterol drugs like pravastatin. Your doctor or pharmacist needs to review your specific medications and may adjust timing or monitoring.

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

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Quercetin with Zinc label
Go deeper

The Full Monographs Behind Quercetin with Zinc’s Ingredients

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

Herb & supplement monograph

Zinc

Interacts with 67 drugs

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but supplements can help correct or prevent a defici...

Read the full Zinc monograph → Herb & supplement monograph

Elderberry

Interacts with 121 drugs

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu symptoms, but the evidence is limited and n...

Read the full Elderberry 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 →
Sources

Sources & How We Checked

Quercetin with Zinc'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 120 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.

Zinc 88 references
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  3. Smith DS, Helzner EC, Nuttall CE Jr, et al. Failure of zinc gluconate in treatment of acute upper respiratory tract infections. Antimicrob Agents Chemother 1989;33:646-8. PubMed
  4. Blondeau JM. Expanded activity and utility of the new fluoroquinolones: a review. Clin Ther 1999;21:3-40. PubMed
  5. Reyes AJ, Olhaberry JV, Leary WP, et al. Urinary zinc excretion, diuretics, zinc deficiency and some side-effects of diuretics. S Afr Med J 1983;64:936-41.
  6. Kugelmas M. Preliminary observation: oral zinc sulfate replacement is effective in treating muscle cramps in cirrhotic patients. J Am Coll Nutr 2000;19:13-5. PubMed
  7. Hebel SK, ed. Drug Facts and Comparisons. 52nd ed. St. Louis: Facts and Comparisons, 1998.
  8. Chan S, Gerson B, Subramaniam S. The role of copper, molybdenum, selenium, and zinc in nutrition and health. Clin Lab Med 1998;18:673-85. DOI
  9. Brewer GJ, Yuzbasiyan-Gurkan V, Johnson V, et al. Treatment of Wilson's disease with zinc: XI. Interaction with other anticopper agents. J Am Coll Nutr 1993;12:26-30. PubMed
  10. Fosmire GJ. Zinc toxicity. Am J Clin Nutr 1990;51:225-7.
  11. Lomaestro BM, Bailie GR. Absorption interactions with fluoroquinolones. 1995 update. Drug Saf 1995;12:314-33. PubMed
  12. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  13. Seelig MS. Auto-immune complications of D-penicillamine - A possible result of zinc and magnesium depletion and of pyridoxine inactivation. J Am Coll Nutr 1982;1:207-14. PubMed
  14. Neuvonen PJ. Interactions with the absorption of tetracyclines. Drugs 1976;11:45-54.. PubMed
  15. Hirt M, Nobel S, Barron E. Zinc nasal gel for the treatment of common cold symptoms: A double-blind, placebo-controlled trial. Ear Nose Throat J 2000;79:778-82.. DOI
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  18. Douglas RM, Miles HB, Moore BW, et al. Failure of effervescent zinc acetate lozenges to alter the course of upper respiratory tract infections in Australian adults. Antimicrob Agents Chemother 1987;31:1263-5. PubMed
  19. Lagiou P, Wuu J, Trichopoulou A, et al. Diet and benign prostatic hyperplasia: a study in Greece. Urology 1999;54:284-90. PubMed
  20. Ewing CI, Gibbs AC, Ashcroft C, David TJ. Failure of oral zinc supplementation in atopic eczema. Eur J Clin Nutr 1991;45:507-10.
  21. 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.
  22. Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss. AREDS report no. 8. Arch Oph
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  24. Godfrey HR, Godfrey NJ, Godfrey JC, Riley D. A randomized clinical trial on the treatment of oral herpes with topical zinc oxide/glycine. Altern Ther Health Med 2001;7:49-56.
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  27. Mossad SB. Effect of zincum gluconicum nasal gel on the duration and symptom severity of the common cold in otherwise healthy adults. QJM 2003;96:35-43. DOI
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  29. Jafek BW, Linschoten M, Murrow BW. Zicam Induced Anosmia. American Rhinologic Society 49th Annual Fall Scientific Meeting abstract. Orlando, Florida. September 20, 2003. http://app.american-rhinologic.org/programs/2003ARSFallProgram071503.pdf (Accessed 24
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  32. Bilici M, Yildirim F, Kandil S, et al. Double-blind, placebo-controlled study of zinc sulfate in the treatment of attention deficit hyperactivity disorder. Prog Neuropsychopharmacol Biol Psychiatry 2004;28:181-90.. PubMed
  33. Polk RE, Healy DP, Sahai J, et al. Effect of ferrous sulfate and multivitamins with zinc on absorption of ciprofloxacin in normal volunteers. Antimicrob Agents Chemother 1989;33:1841-4. PubMed
  34. Mery C, Delrieu F, Ghozlan R, et al. Controlled trial of D-penicillamine in rheumatoid arthritis. Dose effect and the role of zinc. Scand J Rheumatol 1976;5:241-7. PubMed
  35. Penttila O, Hurme H, Neuvonen PJ. Effect of zinc sulfate on the absorption of tetracycline and doxycycline in man. Eur J Clin Pharmacol 1975;9:131-4.
  36. Kondo Y, Yamagata K, Satoh M, et al. Optimal administration schedule of cisplatin for bladder tumor with minimal induction of metallothionein. J Urol 2003;170:2467-70. PubMed
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  38. Wester PO. Urinary zinc excretion during treatment with different diuretics. Acta Med Scand 1980;208:209-12. PubMed
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  41. McBride K, Slotnick B, Margolis FL. Does intranasal application of zinc sulfate produce anosmia in the mouse? An olfactometric and anatomical study. Chem Senses 2003;28:659-70. PubMed
  42. Burd GD. Morphological study of the effects of intranasal zinc sulfate irrigation on the mouse olfactory epithelium and olfactory bulb. Microsc Res Tech 1993;24:195-213. PubMed
  43. Ducray A, Bondier JR, Michel G, et al. Recovery following peripheral destruction of olfactory neurons in young and adult mice. Eur J Neurosci 2002;15:1907-17. PubMed
  44. Mayer AD, Rosenblatt JS. Peripheral olfactory deafferentation of the primary olfactory system in rats using ZnSO4 nasal spray with special reference to maternal behavior. Physiol Behav 1993;53:587-92. PubMed
  45. DeCook CA, Hirsch AR. Anosmia due to inhalational zinc: a case report (abstract). Chem Senses 2000;25:659.
  46. Tisdall FF, Brown A, Defries RD. Persistent anosmia following zinc sulfate nasal spraying. JPed 1938;18:60-2. DOI
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  48. Public Health Advisory. Loss of sense of smell with intranasal cold remedies containing zinc. U.S. Food and Drug Administration, June 16, 2009. Available at: http://www.fda.gov/Drugs/DrugSafety/PublicHealthAdvisories/ucm166059.htm (Accessed 16 June 2009)
  49. Dooren JC. FDA warns against use of Zicam. The Wall Street Journal, June 16, 2009. Available at: http://online.wsj.com/article/SB124516778692319231.html#mod=djemHL?mg=com-wsj (Accessed 16 June 2009).
  50. Alexander TH, Davidson TM. Intranasal zinc and anosmia: the zinc-induced anosmia syndrome. Laryngoscope 2006;116:217-20.
  51. Health Canada / GlaxoSmithKline Consumer Healthcare. Association of long-term, excessive use of zinc-containing Poli-Grip products with myeloneuropathy and blood dyscrasias. February 18, 2010. Available at: http://hc-sc.gc.ca/dhp-mps/alt_formats/pdf/medef
  52. GlaxoSmithKline Consumer Advisory. GlaxoSmithKline (GSK) warns about a potential health risk associated with long-term, excessive use of GSK's zinc-containing denture adhesives Super Polygrip Original, Ultra Fresh and Extra Care. February 18, 2010. Availa
  53. Science M, Johnstone J, Roth DE, et al. Zinc for the treatment of the common cold: a systematic review and meta-analysis of randomized controlled trials. CMAJ 2012;184:E551-61. PubMed
  54. Castilla-Higuero, L., Romero-Gomez, M., Suarez, E., and Castro, M. Acute hepatitis after starting zinc therapy in a patient with presymptomatic Wilson's disease. Hepatology 2000;32(4 Pt 1):877. PubMed
  55. Sharquie, K. E., Najim, R. A., Farjou, I. B., and Al Timimi, D. J. Oral zinc sulphate in the treatment of acute cutaneous leishmaniasis. Clin.Exp.Dermatol. 2001;26(1):21-26. PubMed
  56. Dreno, B., Moyse, D., Alirezai, M., Amblard, P., Auffret, N., Beylot, C., Bodokh, I., Chivot, M., Daniel, F., Humbert, P., Meynadier, J., and Poli, F. Multicenter randomized comparative double-blind controlled clinical trial of the safety and efficacy of
  57. Moore, R. Bleeding gastric erosion after oral zinc sulphate. Br.Med J 3-25-1978;1(6115):754. PubMed
  58. Jafek, B. W., Linschoten, M. R., and Murrow, B. W. Anosmia after intranasal zinc gluconate use. Am J Rhinol. 2004;18(3):137-141. DOI
  59. Simonart, T. and de, Maertelaer, V. Systemic treatments for cutaneous warts: a systematic review. J Dermatolog.Treat. 2012;23(1):72-77. PubMed
  60. Cochran, R. J., Tucker, S. B., and Flannigan, S. A. Topical zinc therapy for acne vulgaris. Int.J Dermatol. 1985;24(3):188-190. DOI
  61. Morgan, A. A. Bleeding gastric erosion after oral zinc sulphate. Br.Med.J. 5-13-1978;1(6122):1283-1284. PubMed
  62. Murphy, J. V. Intoxication following ingestion of elemental zinc. JAMA 6-22-1970;212(12):2119-2120.
  63. Lang, C. J., Rabas-Kolominsky, P., Engelhardt, A., Kobras, G., and Konig, H. J. Fatal deterioration of Wilson's disease after institution of oral zinc therapy. Arch Neurol. 1993;50(10):1007-1008. PubMed
  64. Fjellner, B. Drug-induced lupus erythematosus aggravated by oral zinc therapy. Acta Derm.Venereol. 1979;59(4):368-370. DOI
  65. Varas Lorenzo, M. J. Zinc acexamate and ranitidine in the short- and mid-term management of gastroduodenal ulcers. Curr Ther Res 21986;39:19-29.
  66. Bosch, F. and Jimenez, E. Post-marketing surveillance of zinc acexamate in peptic ulcer treatment. Clin Trials J 1990;27:301-312.
  67. DeCook, C. A. and Hirsch, A. R. Anosmia due to inhalational zinc: a case report (abstract). Chem Senses 2000;25:659.
  68. Crown LA, May JA. Zinc toxicity: denture adhesives, bone marrow failure and polyneuropathy. Tenn Med. 2012 Feb;105(2):39-40, 42.
  69. Dadamio J, Van Tournout M, Teughels W, Dekeyser C, Coucke W, Quirynen M. Efficacy of different mouthrinse formulations in reducing oral malodour: a randomized clinical trial. J Clin Periodontol. 2013 May;40(5):505-13. PubMed
  70. Moyle G, Else L, Jackson A, Back D, Yapa MH, Seymour N, Ringner-Nackter L, Karolia Z, Gazzard B, Boffito M. Coadministration of atazanavir-ritonavir and zinc sulfate: impact on hyperbilirubinemia and pharmacokinetics. Antimicrob Agents Chemother. 2013 Aug PubMed
  71. Zittel S, Ufer F, Gerloff C, Münchau A, Rosenkranz M. Severe myelopathy after denture cream use--is copper deficiency or excess zinc the cause? Clin Neurol Neurosurg. 2014 Jun;121:17-8. PubMed
  72. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  73. Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents: Drug Interactions between Integrase Inhibitors and Other Drugs. AIDSinfo. July 14, 2016. Available at: https://aidsinfo.nih.gov/guidelines/html/1/adult-and-adolescen
  74. Ding Y, Jia YY, Li F, et al. The effect of staggered administration of zinc sulfate on the pharmacokinetics of oral cephalexin. Br J Clin Pharmacol. 2012 Mar;73(3):422-7. PubMed
  75. Fallah R, Sabbaghzadegan S, Karbasi SA, Binesh F. Efficacy of zinc sulfate supplement on febrile seizure recurrence prevention in children with normal serum zinc level: A randomised clinical trial. Nutrition. 2015;31(11-12):1358-61. PubMed
  76. Lazzerini M, Wanzira H. Oral zinc for treating diarrhoea in children. Cochrane Database Syst Rev. 2016;12:CD005436. PubMed
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  79. Yee BE, Richards P, Sui JY, Marsch AF. Serum zinc levels and efficacy of zinc treatment in acne vulgaris: A systematic review and meta-analysis. Dermatol Ther. 2020:e14252. PubMed
  80. Janyajirawong R, Vilaichone RK, Sethasine S. Efficacy of zinc supplement in minimal hepatic encephalopathy: A prospective, randomized controlled study (Zinc-MHE Trial). Asian Pac J Cancer Prev 2021;22(9):2879-2887. PubMed
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See these in context on the Zinc monograph →

Elderberry 6 references
  1. Barak V, Halperin T, Kalickman I. The effect of Sambucol, a black elderberry-based, natural product, on the production of human cytokines: I. Inflammatory cytokines. Eur Cytokine Netw 2001;12:290-6..
  2. Elderberry (Sambucus species). The Poison Plant Patch, Novia Scotia Museum, 2007. Available at: http://museum.gov.ns.ca/poison/?section=species&id=117 (Accessed 16 October 2009).
  3. European elder. Canadian Poisonous Plants Information System. Available at: http://www.cbif.gc.ca/pls/pp/ppack.jump?p_null=all&p_psn=121&p_type=all&p_sci=comm&p_x=px (Accessed 16 October 2009).
  4. Raus K, Pleschka S, Klein P, Schoop R, Fisher P. Effect of an echinacea-based hot drink versus oseltamivir in Influenza treatment: a randomized, double-blind, double-dummy, multicenter, noninferiority clinical trial. . Curr Ther Res Clin Exp. 2015;20;77:6 PubMed
  5. Ramachandran A, Antala D, Pudasainee P, Panginikkod S, Gupta H. A Plausible Association Between the Use of Elderberry and Autoimmune Hepatitis. Cureus 2022;14(4):e24250. PubMed
  6. Agarwal N, Mangla A. Elderberry interaction with pazopanib in a patient with soft-tissue sarcoma: A case report and literature review. Mol Clin Oncol 2024;20(5):36. PubMed

See these in context on the Elderberry monograph →

Quercetin 26 references
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  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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  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.
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  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 →

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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