Drug & supplement interaction

Quercetin + Tigecycline

Tigecycline brand name: Tygacil.

Moderate Interaction
The bottom line Moderate

Quercetin has a moderate interaction with Tigecycline. Theoretically, concomitant use might inhibit the effects of quinolone antibiotics.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Quercetin and Tigecycline

Here is the interaction we found between these two, with the evidence behind it.

Moderate

QUINOLONE ANTIBIOTICS

Why this applies to Tigecycline

Tigecycline falls under QUINOLONE ANTIBIOTICS — the group Quercetin interacts with.

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.
Severity Moderate Likelihood Possible Evidence B

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's something worth knowing if you're getting Tigecycline (Tygacil) for an infection. The concern on file comes from lab studies showing quercetin can bind to a bacterial target called DNA gyrase, which could theoretically blunt how well certain antibiotics kill bacteria. The catch is that this research was done with quinolone antibiotics, which work mainly through DNA gyrase. Tigecycline is actually a tetracycline-class drug, so it kills bacteria a different way (by blocking their protein-making machinery), and it isn't a prodrug.

So this specific worry may not really apply to tigecycline. Still, since you're treating a serious infection, don't add a high-dose quercetin supplement without first checking with your doctor or pharmacist. Better safe than sorry while you're healing.

References
  1. Shoskes DA, Zeitlin SI, Shahed A, Rajfer J. Quercetin in men with category III chronic prostatitis: A preliminary prospective, double-blind, placebo-controlled trial. Urol 1999;54:960-3. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • 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.
Evidence the quality of the studies behind the rating (graded A–D)
  • 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.

Keep it in perspective

Quercetin Also Interacts With Other Medications

Quercetin has 1,168 moderate known drug interactions in our database — the Tigecycline one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Quercetin

Covers the 2,830 medications we’ve checked against Quercetin. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Tigecycline

This page covers Quercetin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tigecycline page lists 98 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Oleander (major), Para-aminobenzoic Acid (paba) (major), Acerola (moderate), Alfalfa (moderate) and Alpha-lipoic Acid (moderate).

By severity: 2 major · 88 moderate · 8 minor.

From our pharmacist’s overview on the Tigecycline page

“Tigecycline (Tygacil) is an intravenous antibiotic usually reserved for serious or resistant infections, and its supplement list deserves real attention. The two major-rated entries come first: oleander, a heart-toxic plant whose compounds may build to dangerous levels with certain antibiotics on board, and PABA, which can blunt the an…”

Reviewed by 2 · Jul 18, 2026

Open the Tigecycline interaction page

One more smart check

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 Tigecycline 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:

How much people look this up

Where Quercetin and Tigecycline 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.

Supplement Quercetin
Top 5%

#47 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Tigecycline
Steady interest

#2,350 of 2,830 medications looked up here in the last 7 days

29 days ago today

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.

Supplement

About Quercetin

What is Quercetin?

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.

Read the full Quercetin monograph & all interactions
Medication

About Tigecycline Injection

What Is Tigecycline Injection Used For?

Brand name: Tygacil

Tygacil (tigecycline for injection) is approved for adults 18 and older to treat three types of serious bacterial infections: complicated skin and skin structure infections, complicated intra-abdominal (stomach and intestinal) infections, and community-acquired bacterial pneumonia (pneumonia caught outside a hospital).

It is not approved for diabetic foot infections or for pneumonia caught in a hospital setting, including ventilator-associated pneumonia — clinical trials showed it did not work well enough for those uses and was associated with higher mortality in patients with ventilator-associated pneumonia.

See full Tigecycline Injection drug information
Keep checking

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.

0Major
1,168Moderate
0Minor
1,661No known interaction
Moderate

1,168 interactions

Showing 60 of 1,168 moderate interactions — see all 1,168 on the Quercetin page.

No interaction 1,661 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

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

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Pharmacist Counseling Corner

Taking Quercetin and Tigecycline Together: Common Questions

Can you take Quercetin with Tigecycline?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Quercetin and Tigecycline interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Tigecycline and Quercetin?

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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.