Drug & supplement interaction

Ostarine + Darunavir

Darunavir brand name: Prezista.

Minor Interaction
The bottom line Minor

Ostarine has a minor interaction with Darunavir. Theoretically, concomitant use of ostarine with CYP3A4 inhibitors could increase the effects and adverse effects of ostarine, although this is unlikely to be clinically significant.

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

Ostarine and Darunavir

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

Minor

CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS

Why this applies to Darunavir

Darunavir falls under CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS — the group Ostarine interacts with.

Theoretically, concomitant use of ostarine with CYP3A4 inhibitors could increase the effects and adverse effects of ostarine, although this is unlikely to be clinically significant.
Ostarine is partially metabolized by CYP3A4. However, clinical research shows that taking itraconazole, a potent inhibitor of CYP3A4, had minimal effects on the levels of ostarine in the body.
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 how this pairing works. Darunavir (Prezista), especially when boosted with ritonavir or cobicistat, is a strong blocker of the CYP3A4 enzyme. Since your body uses CYP3A4 to partly break down Ostarine, in theory darunavir could slow that breakdown and let Ostarine build up a bit, which might mean more of its effects and side effects.

In real life, though, this is unlikely to matter much. When researchers paired Ostarine with itraconazole, an even stronger CYP3A4 blocker, the Ostarine levels barely budged. So the concern here is mostly theoretical. My bigger worry is Ostarine itself, which is an unapproved SARM linked to liver injury, something that already overlaps with HIV care. Please talk with your pharmacist or doctor before combining them.

References
  1. Coss CC, Jones A, Dalton JT. Pharmacokinetic drug interactions of the selective androgen receptor modulator GTx-024 (enobosarm) with itraconazole, rifampin, probenecid, celecoxib and rosuvastatin. Invest New Drugs 2016;34(4):458-67. 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

Ostarine Also Interacts With Other Medications

Ostarine has 440 moderate, 170 minor known drug interactions in our database — the Darunavir 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 Ostarine

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

From our Q&A

Questions About Ostarine or Darunavir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Ostarine or Darunavir, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Darunavir

This page covers Ostarine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Darunavir page lists 145 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 102 moderate · 40 minor.

From our pharmacist’s overview on the Darunavir page

“Someone on darunavir (Prezista) for HIV depends on steady drug levels to keep the virus suppressed, and this list of 145 interacting supplements calls for real caution before adding any of them. Most of the traffic runs through the CYP3A4 enzyme, in both directions.”

Reviewed by 2 · Jul 18, 2026

Open the Darunavir interaction page

One more smart check

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

We hold 33 real supplement products containing Ostarine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ostarine. Your product may carry other ingredients that interact with Darunavir too, on top of Ostarine — 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 Ostarine and Darunavir 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 Ostarine
Steady interest

#1,257 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Darunavir
Steady interest

#2,772 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 Ostarine

What is Ostarine?

  • Muscle building
  • Athletic performance
  • Fat loss / body recomposition
  • Bodybuilding cycles

Ostarine (also called MK-2866 or enobosarm) is an experimental, unapproved drug known as a SARM (selective androgen receptor modulator), not a true dietary supplement. It is not approved by the FDA, is banned in sports, and has been linked to liver injury and other serious harms, so it is not recommended for general use.

Read the full Ostarine monograph & all interactions
Medication

About Darunavir

What Is Darunavir Used For?

Brand name: Prezista

Darunavir treats HIV-1 infection in adults and in children who are at least 3 years old and weigh at least 10 kg (about 22 lbs). It is not a cure for HIV, but it is used as part of a combination antiretroviral regimen to control the virus.

Darunavir must always be taken together with ritonavir — that pairing is required for darunavir to work properly. Both Prezista (brand name) and generic darunavir tablets are approved for this use. Prezista is also available as an oral suspension, which is particularly useful for younger or smaller patients.

See full Darunavir drug information
Keep checking

Other Drugs & Ostarine

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

0Major
440Moderate
170Minor
2,219No known interaction
Moderate

440 interactions

Showing 60 of 440 moderate interactions — see all 440 on the Ostarine page.

Minor

170 interactions

Showing 60 of 170 minor interactions — see all 170 on the Ostarine page.

No interaction 2,219 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 Ostarine and Darunavir Together: Common Questions

Can you take Ostarine with Darunavir?
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 Ostarine and Darunavir 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

Still Have a Question About Darunavir and Ostarine?

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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.