Drug & supplement interaction

Ostarine + Aprepitant

Aprepitant brand names: Emend, Cinvanti.

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

Aprepitant falls into 2 drug categories that Ostarine can interact with; the most serious is rated moderate. Theoretically, concomitant use of ostarine with CYP3A4 inducers could decrease the clinical effects of ostarine.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Ostarine and Aprepitant

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Ostarine interacts with whole categories of medication. Aprepitant falls into 2 of those categories, so it can interact with Ostarine in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CYTOCHROME P450 3A4 (CYP3A4) INDUCERS

1 of 2

Why this applies to Aprepitant

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

Theoretically, concomitant use of ostarine with CYP3A4 inducers could decrease the clinical effects of ostarine.
Ostarine is partially metabolized by CYP3A4. Clinical research shows that taking rifampin, a potent inducer of CYP3A4, reduces the maximum plasma concentration of ostarine by 23% and the area under the curve by 43%.
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 the gist of this pairing. Aprepitant can act as a mild inducer of the CYP3A4 enzyme, meaning it can nudge your body to clear certain things a little faster. Since Ostarine is partly broken down by that same enzyme, using the two together could lower your Ostarine levels and weaken whatever effect you're hoping to get from it. In one study, a much stronger inducer (rifampin) dropped Ostarine blood levels by roughly 23 to 43 percent, so aprepitant's effect would likely be smaller and is mostly theoretical.

Honestly, my bigger concern isn't the interaction itself. Ostarine is an unapproved SARM that has been linked to liver injury, and aprepitant is given during chemotherapy, when your liver is already under stress. Please loop in your oncology team or pharmacist before mixing anything with your cancer treatment.

Contact Dr. Brian directly if you have additional questions on this interaction
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
Minor

CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS

2 of 2

Aprepitant also falls under CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS.

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 the gist for this pairing. Aprepitant (Emend) acts as a mild blocker of an enzyme called CYP3A4, and Ostarine is partly cleared by that same enzyme. On paper, slowing that enzyme could let a little more Ostarine linger in your body, which might nudge up its effects and its risks. Since Ostarine has been tied to liver injury and other serious harms, that's not something to brush off.

That said, the real-world signal here is weak. Studies using a much stronger CYP3A4 blocker barely changed Ostarine levels, so this is mostly theoretical and unlikely to matter much. The bigger concern is Ostarine itself, an unapproved, banned SARM I wouldn't recommend. If you're getting chemo and using it, please loop in your oncology pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
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 439 moderate, 171 minor known drug interactions in our database — the Aprepitant one above is among them. If you take anything else, check it against the full list below.

Moderate 439 Minor 171 No known interaction 2,220 (incl. Aprepitant)
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.

Everything else you take

See Every Supplement That Interacts With Aprepitant

This page covers Ostarine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aprepitant page lists 158 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 · 116 moderate · 39 minor.

From our pharmacist’s overview on the Aprepitant page

“Aprepitant (Emend, Cinvanti) keeps chemotherapy patients from vomiting, so a supplement that undoes it mid-cycle is a problem, and I read this list with genuine vigilance. Nearly all 158 entries touch CYP3A4, the liver enzyme that clears aprepitant.”

Reviewed by 2 · Jul 18, 2026

Open the Aprepitant 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 Aprepitant 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 Aprepitant 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

#1,283 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Aprepitant
Top 25%

#383 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 Aprepitant

What Is Aprepitant Used For?

Brand names: Emend, Cinvanti

Aprepitant is used to prevent nausea and vomiting — not to treat it once it has started. It is always used alongside other anti-nausea medicines, not on its own.

EMEND capsules (oral) are approved for adults and children 12 and older to prevent nausea from highly or moderately emetogenic (nausea-causing) chemotherapy. EMEND for oral suspension extends that same use down to children as young as 6 months. CINVANTI (IV injection) is approved for adults only, for chemotherapy-related nausea. APONVIE (IV emulsion) is approved for adults to prevent postoperative nausea and vomiting (PONV) — nausea after surgery. Aprepitant capsules (generic) are approved for adults and children 12 and older for chemotherapy-related nausea, and also for adults to prevent PONV.

See full Aprepitant 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
439Moderate
171Minor
2,219No known interaction
439 Moderate 171 Minor 2,219 No interaction
Moderate

439 interactions

Showing 60 of 439 moderate interactions — see all 439 on the Ostarine page.

Minor

171 interactions

Showing 60 of 171 minor interactions — see all 171 on the Ostarine page.

No interaction 2,219 drugs checked — show the list

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

Showing the 60 most looked-up of 2,219 medications checked with no known interaction — see the full Ostarine list.

See the full Ostarine interactions page
See every supplement checked against Aprepitant, 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
Ostarine monograph › Uses, safety, and every drug interaction in one place Aprepitant supplement interactions › Every supplement checked against Aprepitant, ranked by severity Aprepitant 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 Ostarine and Aprepitant Together: Common Questions

Can you take Ostarine with Aprepitant?
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.
Why are there 2 interactions listed for Ostarine and Aprepitant?
Aprepitant belongs to more than one drug category, and Ostarine interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Ostarine and Aprepitant 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 Aprepitant 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.