Drug & supplement interaction

Tribulus + Simvastatin, Sitagliptin

Simvastatin, Sitagliptin brand name: Juvisync.

Moderate Interaction
The bottom line Moderate

Tribulus has a moderate interaction with Simvastatin, Sitagliptin. Taking tribulus with antidiabetes drugs might increase the risk of hypoglycemia.

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

Tribulus and Simvastatin, Sitagliptin

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Simvastatin, Sitagliptin

Simvastatin, Sitagliptin falls under ANTIDIABETES DRUGS — the group Tribulus interacts with.

Taking tribulus with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research shows that Tribulus can lower blood glucose levels in adults with type 2 diabetes who are taking antidiabetes medications.
Severity Moderate Likelihood Possible Evidence D

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

The medication you're asking about (Juvisync) is a combo pill that pairs simvastatin, a cholesterol-lowering statin, with sitagliptin, a diabetes drug that helps your body manage blood sugar. The piece that matters here is the sitagliptin part. Tribulus has been shown in some studies to lower blood glucose, so layering it on top of a blood-sugar medication could push your levels down a little too far.

In real life, that might look like feeling shaky, sweaty, dizzy, lightheaded, or unusually hungry. It's worth keeping an eye on, especially if you're already monitoring your sugars. The statin side of the pill isn't really the concern with Tribulus. Don't stop anything on your own, but please check with your pharmacist or doctor first, and watch your readings if you do combine them.

References
  1. Samani NB, Jokar A, Soveid M, Heydari M, Mosavat SH. Efficacy of the hydroalcoholic extract of Tribulus terrestris on the serum glucose and lipid profile of women with diabetes mellitus: a double-blind randomized placebo-controlled clinical trial. J Evid

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

Tribulus Also Interacts With Other Medications

Tribulus has 258 moderate known drug interactions in our database — the Simvastatin, Sitagliptin 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 Tribulus

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

Everything else you take

See Every Supplement That Interacts With Simvastatin, Sitagliptin

This page covers Tribulus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Simvastatin, Sitagliptin page lists 362 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Apple (major), Beer (major), Grapefruit (major) and Siberian Cocklebur (major).

By severity: 8 major · 304 moderate · 50 minor.

From our pharmacist’s overview on the Simvastatin, Sitagliptin page

“Juvisync pairs simvastatin for cholesterol with sitagliptin for type 2 diabetes, and that combination carries 362 supplement interactions on file, eight rated major, so read this page with real care rather than a quick skim. Grapefruit stands out as the everyday hazard; it blocks the enzyme that clears simvastatin, raising statin level…”

Reviewed by 2 · Jul 18, 2026

Open the Simvastatin, Sitagliptin interaction page

One more smart check

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

We hold 1,680 real supplement products containing Tribulus, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Tribulus. Your product may carry other ingredients that interact with Simvastatin, Sitagliptin too, on top of Tribulus — 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 Tribulus and Simvastatin, Sitagliptin 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 Tribulus
Top 10%

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

29 days ago today
Medication Simvastatin, Sitagliptin
Steady interest

#1,669 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 Tribulus

What is Tribulus?

Tribulus
  • Low libido and sexual function
  • Athletic performance and muscle building
  • Testosterone support
  • Male and female fertility
  • General 'vitality' or wellness

Tribulus is a plant supplement most often marketed to boost libido, testosterone, and athletic performance, but the human evidence behind these claims is weak and inconsistent. It is generally well tolerated by healthy adults in the short term, but it should be avoided during pregnancy and breastfeeding and discussed with your pharmacist or doctor before use.

Read the full Tribulus monograph & all interactions
Keep checking

Other Drugs & Tribulus

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

0Major
258Moderate
0Minor
2,571No known interaction
Moderate

258 interactions

Showing 60 of 258 moderate interactions — see all 258 on the Tribulus page.

No interaction 2,571 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 Tribulus and Simvastatin, Sitagliptin Together: Common Questions

Can you take Tribulus with Simvastatin, Sitagliptin?
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 Tribulus and Simvastatin, Sitagliptin 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 Simvastatin, Sitagliptin and Tribulus?

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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.