Drug & supplement interaction

Oolong Tea + Rosiglitazone Maleate

Rosiglitazone Maleate brand name: Avandia.

Minor Interaction
Medically reviewed by · Updated September 2026
The bottom line Minor

Oolong Tea has a minor interaction with Rosiglitazone Maleate. Theoretically, taking oolong tea with antidiabetes drugs might interfere with blood glucose control.

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

Oolong Tea and Rosiglitazone Maleate

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

Minor

ANTIDIABETES DRUGS

Why this applies to Rosiglitazone Maleate

Rosiglitazone Maleate falls under ANTIDIABETES DRUGS — the group Oolong Tea interacts with.

Theoretically, taking oolong tea with antidiabetes drugs might interfere with blood glucose control.
Oolong tea contains caffeine. Reports claim that caffeine might increase or decrease blood glucose levels.
Severity Minor Likelihood Unlikely Evidence B

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

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

Here's the honest picture with oolong tea and your Avandia (rosiglitazone). This is a pretty minor, mostly theoretical concern. The thinking is that the caffeine in oolong tea can nudge blood sugar in either direction, which could slightly throw off the steady blood sugar control your rosiglitazone is working to achieve.

In practice, a cup or two of oolong tea is very unlikely to cause a problem for most people. Rosiglitazone works by making your body more sensitive to insulin, and caffeine doesn't change how that drug is processed. I'd just keep an eye on your usual readings if you suddenly start drinking a lot of tea or take concentrated caffeine supplements, and watch for shaky, sweaty low-sugar feelings or higher-than-normal numbers. If anything looks off, loop in your pharmacist or doctor before making changes.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9. PubMed
  2. Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399-403. PubMed
  3. Baer DJ, Novotny JA, Harris GK, Stote K, Clevidence B, Rumpler WV. Oolong tea does not improve glucose metabolism in non-diabetic adults. Eur J Clin Nutr 2011;65(1):87-93. 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

Oolong Tea Also Interacts With Other Medications

Oolong Tea has 8 major, 518 moderate, 125 minor known drug interactions in our database — the Rosiglitazone Maleate one above is one of them. If you take anything else, check it against the full list below.

Major 8 Moderate 518 Minor 125 No known interaction 2,179 (incl. Rosiglitazone Maleate)
Taking anything else?

Check Another of Your Medications Against Oolong Tea

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

Everything else you take

See Every Supplement That Interacts With Rosiglitazone Maleate

This page covers Oolong Tea only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Rosiglitazone Maleate page lists 314 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Siberian Cocklebur (major), Wine (major) and Acai (moderate).

By severity: 4 major · 266 moderate · 44 minor.

From our pharmacist’s overview on the Rosiglitazone Maleate page

“Rosiglitazone (Avandia) lowers blood sugar in type 2 diabetes, and most of the 314 supplements and herbs on this page pull on that same lever. Some 239 can move blood glucose on their own, so adding one risks hypoglycemia, the shakiness, sweating, and confusion of sugar falling too low.”

Reviewed by 2 · Jul 18, 2026

Open the Rosiglitazone Maleate interaction page

One more smart check

Taking Oolong Tea as Part of a Dietary Supplement Product? Check It for Interactions

We hold 75 real supplement products containing Oolong Tea, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Oolong Tea. Your product may carry other ingredients that interact with Rosiglitazone Maleate too, on top of Oolong Tea — 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 Oolong Tea and Rosiglitazone Maleate 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 Oolong Tea
Steady interest

#1,114 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Rosiglitazone Maleate
Steady interest

#1,768 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 Oolong Tea

What is Oolong Tea?

  • Weight management
  • Mental alertness and energy
  • Heart health
  • Blood sugar support
  • Antioxidant support

Oolong tea is a traditional partially oxidized tea made from the same plant as green and black tea, and it provides caffeine and plant antioxidants. As a beverage it is generally considered safe for most healthy adults in moderate amounts, but evidence for specific health benefits like weight loss or blood sugar control is limited. If you have heart, blood pressure, or caffeine-sensitivity concerns, talk with your pharmacist or doctor.

Read the full Oolong Tea monograph & all interactions
Medication

About Rosiglitazone

What Is Rosiglitazone Used For?

Brand name: Avandia

  • Rosiglitazone is used along with a diet and exercise program and sometimes with one or more other medications to treat type 2 diabetes (condition in which the body does not use insulin normally and therefore cannot control the amount of sugar in the blood). Rosiglitazone is in a class of medications called thiazolidinediones. It works by increasing the body's sensitivity to insulin, a natural substance that helps control blood sugar levels. Rosiglitazone is not used to treat type 1 diabetes (condition in which the body does not produce insulin and therefore cannot control the amount of sugar in the blood) or diabetic ketoacidosis (a serious condition that may occur if high blood sugar is not treated).

  • Over time, people who have diabetes and high blood sugar can develop serious or life-threatening complications, including heart disease, stroke, kidney problems, nerve damage, and eye problems. Taking medication(s), making lifestyle changes (e.g., diet, exercise, quitting smoking), and regularly checking your blood sugar may help to manage your diabetes and improve your health. This therapy may also decrease your chances of having a heart attack, stroke, or other diabetes-related complications such as kidney failure, nerve damage (numb, cold legs or feet; decreased sexual ability in men and women), eye problems, including changes or loss of vision, or gum disease. Your doctor and other healthcare providers will talk to you about the best way to manage your diabetes.

See full Rosiglitazone drug information
Keep checking

Other Drugs & Oolong Tea

Browse every other medication we’ve checked against Oolong Tea — both the ones with a known interaction and the ones without. Select any drug for the full detail.

8Major
518Moderate
125Minor
2,178No known interaction
8 Major 518 Moderate 125 Minor 2,178 No interaction
Major

8 interactions

Moderate

518 interactions

Showing 60 of 518 moderate interactions — see all 518 on the Oolong Tea page.

Minor

125 interactions

Showing 60 of 125 minor interactions — see all 125 on the Oolong Tea page.

No interaction 2,178 drugs checked — show the list

We also checked Oolong Tea against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,178 medications checked with no known interaction — see the full Oolong Tea list.

See the full Oolong Tea interactions page
See every supplement checked against Rosiglitazone Maleate, ranked by severity
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

Keep exploring
Oolong Tea monograph › Uses, safety, and every drug interaction in one place Rosiglitazone Maleate supplement interactions › Every supplement checked against Rosiglitazone Maleate, ranked by severity Rosiglitazone drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Oolong Tea and Rosiglitazone Maleate Together: Common Questions

Can you take Oolong Tea with Rosiglitazone Maleate?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Oolong Tea and Rosiglitazone Maleate interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

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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.