Quercetin + Bisoprolol, Hydrochlorothiazide
Bisoprolol, Hydrochlorothiazide brand name: Ziac.
Bisoprolol, Hydrochlorothiazide falls into 4 drug categories that Quercetin can interact with; the most serious is rated moderate. Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
Read the full interaction reportQuercetin and Bisoprolol, Hydrochlorothiazide
These two interact in 4 distinct ways. Each one is explained separately below.
Why Are There 4 Interactions?
Quercetin interacts with whole categories of medication. Bisoprolol, Hydrochlorothiazide falls into 4 of those categories, so it can interact with Quercetin in 4 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).
ANTIHYPERTENSIVE DRUGS
1 of 4Why this applies to Bisoprolol, Hydrochlorothiazide
Bisoprolol, Hydrochlorothiazide falls under ANTIHYPERTENSIVE DRUGS — the group Quercetin interacts with.
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.
Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
Ziac is a combo pill that already lowers blood pressure two ways: bisoprolol (a beta blocker) slows your heart and eases its workload, while hydrochlorothiazide (a water pill) helps your body shed extra fluid and salt. Quercetin isn't broken down by your liver into something here. Instead, the concern is simpler: quercetin may modestly lower blood pressure on its own, so stacking it on top of Ziac could nudge your numbers down a little too far.
If that happens, you might feel dizzy, lightheaded, tired, or wobbly when standing up quickly. Honestly, this is a theoretical add-on effect with only modest evidence, and food amounts of quercetin are unlikely to matter. Still, if you take high-dose supplements, mention it to your pharmacist or doctor and keep an eye on your readings.
- Edwards RL, Lyon T, Litwin SE, et al. Quercetin reduces blood pressure in hypertensive subjects. J Nutr 2007;137:2405-11.
- 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
ORGANIC ANION TRANSPORTER 3 (OAT3) SUBSTRATES
2 of 4Bisoprolol, Hydrochlorothiazide also falls under ORGANIC ANION TRANSPORTER 3 (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.
Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
Here's the gist with Ziac, which combines bisoprolol (a beta blocker) and hydrochlorothiazide (a water pill). Your kidneys use a transporter called OAT3 to help move certain drugs out of your body. In lab dish studies, quercetin seems to block OAT3 fairly strongly. If that happened in real life, the hydrochlorothiazide piece could hang around a bit longer, which in theory could nudge its effects up a little, think more urination, dizziness, or low potassium.
Now the honest part: this is only test-tube data and has never been reported in actual people. Quercetin from food (apples, onions, berries) is very unlikely to matter. Before starting a concentrated supplement, just run it by your pharmacist or doctor.
- 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
ORGANIC ANION TRANSPORTER 1 (OAT1) SUBSTRATES
3 of 4Bisoprolol, Hydrochlorothiazide also falls under ORGANIC ANION TRANSPORTER 1 (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.
Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
Here's the gist with Ziac, which combines bisoprolol (a beta blocker) and hydrochlorothiazide (a water pill). Your kidneys use a transporter called OAT1 to help shuttle certain drugs, including the hydrochlorothiazide part, out into your urine. In lab dish studies, quercetin appears to block that transporter. If that played out in real life, the thiazide could hang around a bit longer and act a little stronger.
What might that look like? Possibly more frequent urination, lightheadedness, low potassium or sodium, or a bigger drop in blood pressure. I want to be honest, though: this is theoretical and has only been seen in test tubes, never reported in people. Food amounts of quercetin almost certainly don't matter. Before starting a concentrated supplement, just run it by your pharmacist or doctor.
- 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
CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES
4 of 4Bisoprolol, Hydrochlorothiazide also falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES.
In vitro research show that quercetin inhibits CYP2D6. This effect has not been reported in humans.
Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
Ziac combines bisoprolol (a beta-blocker) with hydrochlorothiazide (a water pill). The bisoprolol part is partly cleared by a liver enzyme called CYP2D6. In test-tube studies, quercetin can slow that enzyme down. In theory, that could let a little more bisoprolol build up in your system, which might nudge its effects up a notch, things like a slower heart rate, lower blood pressure, lightheadedness, or feeling unusually tired.
Here is the reassuring part: this comes only from lab research and has not been seen in real people. Everyday food amounts of quercetin (apples, onions, berries) are very unlikely to matter. Concentrated supplements are the bigger question mark. Before starting a high-dose quercetin product, just run it by your pharmacist or doctor.
- 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
- 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
What These Ratings Mean
Every interaction above is graded three ways — here’s the key to each label.
Clinically significant. Avoid the combination, or use only under close professional supervision.
Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.
Generally not serious. Be aware of it and mention it to your pharmacist.
- LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
- ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
- PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
- UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
- AHigh-quality meta-analysis (quantitative systematic review).
- BCase-control study.
- CConsensus.
- DAnecdotal evidence.
These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.
Quercetin Also Interacts With Other Medications
Quercetin has 1,168 moderate known drug interactions in our database — the Bisoprolol, Hydrochlorothiazide one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Quercetin
We haven’t checked that one against Quercetin yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Quercetin. Pick one to open its full report.
See Every Supplement That Interacts With Bisoprolol, Hydrochlorothiazide
This page covers Quercetin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Bisoprolol, Hydrochlorothiazide page lists 276 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Asarabacca (major) and Dolomite (major).
By severity: 11 major · 234 moderate · 31 minor.
From our pharmacist’s overview on the Bisoprolol, Hydrochlorothiazide page
“This is one of the supplement lists I would read closely before adding anything alongside bisoprolol and hydrochlorothiazide (Ziac). The combination already lowers blood pressure two ways, and most of these interactions push on those same levers, either dropping pressure further or acting like extra diuretics that compound potassium an…”
Reviewed by 2 · Jul 18, 2026
Taking Quercetin as Part of a Dietary Supplement Product? Check It for Interactions
We hold 4,589 real supplement products containing Quercetin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Quercetin. Your product may carry other ingredients that interact with Bisoprolol, Hydrochlorothiazide too, on top of Quercetin — and those would not show on this page. Find your product and we’ll check every ingredient on its label:
Where Quercetin and Bisoprolol, Hydrochlorothiazide Sit Against Everything Else
Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.
#47 of 1,452 supplements looked up here in the last 7 days
#684 of 2,830 medications looked up here in the last 7 days
Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.
About Quercetin
What is Quercetin?
- Seasonal allergies
- Antioxidant support
- Heart and blood pressure health
- Anti-inflammatory support
- Immune support
- Exercise recovery
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 pressure, and inflammation, strong human evidence is limited for most uses. It is generally well tolerated in food amounts, but talk to your pharmacist or doctor before taking high-dose supplements.
Other Drugs & Quercetin
Browse every other medication we’ve checked against Quercetin — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
1,168 interactions
- Diclofenac Sodium ›
- Diltiazem ›
- Nifedipine ›
- Ibuprofen ›
- Aspirin ›
- Hydrocortisone ›
- Insulin (rdna) ›
- Naproxen ›
- Doxycycline ›
- Erythromycin ›
- Estradiol ›
- Minocycline ›
- Propranolol ›
- Tetracycline ›
- Lidocaine ›
- Ranitidine ›
- Hydrochlorothiazide ›
- Norethindrone ›
- Testosterone ›
- Verapamil ›
- Levonorgestrel ›
- Prednisone ›
- Quinidine ›
- Cyclosporine ›
- Dexamethasone ›
- Glyburide ›
- Insulin (pork) ›
- Triazolam ›
- Zopiclone ›
- Ciprofloxacin ›
- Colchicine ›
- Fentanyl ›
- Flurbiprofen ›
- Isotretinoin ›
- Oxybutynin ›
- Oxycodone ›
- Phenytoin ›
- Prednisolone ›
- Tacrolimus ›
- Temazepam ›
- Triamcinolone ›
- Apomorphine ›
- Budesonide ›
- Carbamazepine ›
- Ceftazidime ›
- Clindamycin ›
- Dextromethorphan ›
- Diclofenac Potassium ›
- Doxorubicin ›
- Fluticasone ›
- Formoterol ›
- Hydralazine ›
- Indomethacin ›
- Insulin (human) ›
- Miconazole ›
- Morphine Sulfate ›
- Salsalate ›
- Trimipramine ›
- Acyclovir ›
- Amphetamine ›
Showing 60 of 1,168 moderate interactions — see all 1,168 on the Quercetin page.
No interaction 1,661 drugs checked — show the list
We also checked Quercetin against these medications and found no known interaction in our sources. Open any page to confirm.
- Levothyroxine ›
- Methylphenidate ›
- Rosuvastatin ›
- Escitalopram ›
- Acetaminophen ›
- Docusate ›
- Hydroxyurea ›
- Sumatriptan ›
- Bupropion ›
- Amoxicillin ›
- Bendamustine ›
- Lamotrigine ›
- Gabapentin ›
- Pregabalin ›
- Azithromycin ›
- Methylene Blue ›
- Levothyroxine, Liothyronine ›
- Cyclopentolate ›
- Roxithromycin ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Pegunigalsidase Alfa-iwxj ›
- Daptomycin ›
- Hexobarbitone ›
- Dexmethylphenidate ›
- Levothyroxine Sodium ›
- Levetiracetam ›
- Factor 7a ›
- Phentermine, Topiramate ›
- Thyroid Hormone ›
- Carbidopa, Levodopa ›
- Mitomycin ›
- Levodopa ›
- Ezetimibe ›
- Phenylephrine ›
- Vancomycin ›
- Lenvatinib ›
- Hethylphenidate Hcl ›
- Dirithromycin ›
- Pentobarbitone ›
- Bentoquatam ›
- Hydroxychloroquine ›
- Procainamide ›
- Amoxicillin, Clavulanate Potassium ›
- Tenecteplase ›
- Azelaic Acid ›
- Triptorelin ›
- Dextrothyroxine ›
- Lomustine ›
- Pizotifen ›
- Tocainide ›
- Sodium Valproate ›
- Rocuronium ›
- Succimer ›
- Mitomycin C ›
- Lorazepam ›
- Paracetamol ›
- Halothane ›
- Chenodiol ›
- Desflurane ›
- Gestodene ›
Showing the 60 most looked-up of 1,661 medications checked with no known interaction — see the full Quercetin list.
Sources & How We Checked
Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference for vitamins, herbs and supplements — the basis for our interaction data.
- MedlinePlus, U.S. National Library of Medicine — NIH consumer drug information, used for the medication overviews.
- NIH Dietary Supplement Label Database (DSLD) — Official supplement product labels.
Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.
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
Bisoprolol, Hydrochlorothiazide Is Linked to Lower Levels of 7 Nutrients
Natural Medicines records Bisoprolol, Hydrochlorothiazide as a medicine that can lower these. This is not an interaction with Quercetin — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:
Read the full Bisoprolol, Hydrochlorothiazide nutrient depletion report ›
Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.
Taking Quercetin and Bisoprolol, Hydrochlorothiazide Together: Common Questions
Can you take Quercetin with Bisoprolol, Hydrochlorothiazide?
Why are there 4 interactions listed for Quercetin and Bisoprolol, Hydrochlorothiazide?
How serious is the Quercetin and Bisoprolol, Hydrochlorothiazide interaction?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Still Have a Question About Bisoprolol, Hydrochlorothiazide and Quercetin?
Our pharmacists answer your medication & supplement questions — free.
This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.