Drug & supplement interaction

Ostarine + Erlotinib

Erlotinib brand name: Tarceva.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 27, 2026
The bottom line No known interaction

We found no known interaction between Ostarine and Erlotinib in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Erlotinib states a food rule worth keeping to, and the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Ostarine and Erlotinib

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Erlotinib and Ostarine in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Ostarine safety at a glance

Ostarine overall Avoid Ostarine is an unapproved investigational drug with documented safety risks and no FDA approval.
Pregnancy Avoid It affects hormone pathways and must be avoided during pregnancy.
Breastfeeding Avoid There is no safety data, so avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Erlotinib and Ostarine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Erlotinib

Interactions in our licensed database are recorded against drug classes, not just single drug names. Erlotinib is filed under 2 classifications — including oral drugs. Ostarine has documented interactions with 6 drug classes — the most serious being cytochrome p450 3a4 (cyp3a4) inducers (moderate), hepatotoxic drugs (moderate) and probenecid (benemid) (moderate) — and none of Erlotinib’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Ostarine Does Interact With Other Medications

Ostarine has 440 moderate, 171 minor known drug interactions in our database — Erlotinib isn’t one of them. If you take anything else, check it against the full list below.

Moderate 440 Minor 171 No known interaction 2,219 (incl. Erlotinib)
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.

What to actually watch for

No Interaction Found — But Data Suggests Ostarine and Erlotinib May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. 7 of them are worth acting on rather than waiting out — marked below.

  • Severe muscle breakdown Worth acting on Additional detail

    Ostarine

    “Orally, in a 12-week study of healthy elderly patients taking ostarine 1-3 mg daily, back pain was reported in 25% of patients. However, in a 16-week study of cancer patients taking ostarine 1-3 mg daily, back pain occurred at a similar rate with ostarine and placebo.

    In one case, a 43-year-old male taking ostarine and cardarine to increase muscle mass presented with several symptoms, including myalgia and rhabdomyol…”

    Ostarine · Natural Medicines adverse-effect record, reported in back pain.

    3 sources cited
    1. 98833. Dalton JT, Barnette KG, Bohl CE, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II tri
    2. 98832. Dobs AS, Boccia RV, Croot CC, et al. Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. Lancet Oncol 2013;14(4):335-45. PubMed
    3. 111382. Kintz P, Gheddar L, Paradis C, et al. Peroxisome Proliferator-Activated Receptor Delta Agonist (PPAR- d) and Selective Androgen Receptor Modulator (SARM) Abuse: Clinical, Analytical and Biological Data in a Case Involving a Poisonous Combination of GW1516

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • A heart attack Worth acting on Additional detail

    Ostarine

    “Orally, in a 12-week study of healthy elderly patients taking ostarine daily, high-density lipoprotein (HDL) cholesterol levels decreased by 9 mg/dL and 15 mg/dL with ostarine 1 mg and 3 mg, respectively, when compared with placebo. Theoretically, reductions in HDL reported with ostarine could potentially increase the risk for adverse cardiovascular effects. In fact, the U.S.”

    Ostarine · Natural Medicines adverse-effect record, reported in myasthenia gravis.

    5 sources cited
    1. 98833. Dalton JT, Barnette KG, Bohl CE, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II tri
    2. 94879. Warning Letter: Ironmag Labs 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582464.htm Accessed: November 1, 2017
    3. 94880. Warning Letter: Panther Sports Nutrition 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm581630.htm. Accessed: November 1, 2017
    4. 94881. Warning Letter: Infantry Labs LLC 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582685.htm. Accessed: November 1, 2017
    5. 98840. FDA. FDA Warns against using SARMs in body building products. October 2017. Available at: https://www.fda.gov/newsevents/newsroom/fdainbrief/ucm583021.htm.

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • A low platelet count / Anemia Worth acting on Additional detail

    Ostarine

    “Orally, in a 16-week study of cancer patients taking ostarine 1-3 mg daily, anemia and thrombocytopenia were reported more frequently with ostarine than with placebo, although the rate of occurrence in both groups was similar.”

    Ostarine · Natural Medicines adverse-effect record, reported in anemia.

    1 source cited
    1. 98832. Dobs AS, Boccia RV, Croot CC, et al. Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. Lancet Oncol 2013;14(4):335-45. PubMed

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • Shortness of breath / A higher chance of infection Worth acting on Additional detail

    Ostarine

    “Orally, in a 16-week study of cancer patients taking ostarine 1-3 mg daily, pneumonia occurred more frequently with ostarine than with placebo. Cough and dyspnea were also reported, but at rates slightly lower than placebo. In a 12-week study of healthy elderly patients taking ostarine 1-3 mg daily, cough occurred more frequently with ostarine than with placebo.”

    Ostarine · Natural Medicines adverse-effect record, reported in cancer.

    2 sources cited
    1. 98832. Dobs AS, Boccia RV, Croot CC, et al. Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. Lancet Oncol 2013;14(4):335-45. PubMed
    2. 98833. Dalton JT, Barnette KG, Bohl CE, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II tri

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • Liver problems Worth acting on Additional detail

    Ostarine

    “Orally, in a 16-week study of cancer patients taking ostarine 1-3 mg daily, a transient increase in alanine aminotransferase (ALT) of 2- to 4-times the upper limit of normal occurred in 7.4% of patients taking ostarine 3 mg.”

    Ostarine · Natural Medicines adverse-effect record, reported in anorexia.

    6 sources cited
    1. 98832. Dobs AS, Boccia RV, Croot CC, et al. Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. Lancet Oncol 2013;14(4):335-45. PubMed
    2. 98833. Dalton JT, Barnette KG, Bohl CE, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II tri
    3. 94879. Warning Letter: Ironmag Labs 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582464.htm Accessed: November 1, 2017
    4. 94880. Warning Letter: Panther Sports Nutrition 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm581630.htm. Accessed: November 1, 2017
    5. 94881. Warning Letter: Infantry Labs LLC 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582685.htm. Accessed: November 1, 2017
    6. 106197. Bedi H, Hammond C, Sanders D, Yang HM, Yoshida EM. Drug-induced liver injury from enobosarm (ostarine), a selective androgen receptor modulator. ACG Case Rep J 2021;8(1):e00518. PubMed

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • Weight loss Additional detail

    Ostarine

    Recorded for Ostarine in the same Natural Medicines adverse-effect record shown under Liver problems above.

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • Back pain Additional detail

    Ostarine

    Recorded for Ostarine in the same Natural Medicines adverse-effect record shown under Severe muscle breakdown above.

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

  • Cough Additional detail

    Ostarine

    Recorded for Ostarine in the same Natural Medicines adverse-effect record shown under Shortness of breath / A higher chance of infection above.

    Erlotinib

    Listed in the ADVERSE REACTIONS section of the FDA label for Erlotinib. Read the label on DailyMed ›

Showing the 10 most notable of 19 shared effects — ranked by how unusual each one is, not just whether both lists mention it.

Reported for Ostarine but not commonly for Erlotinib: stomach pain, constipation and yellowing of the skin or eyes.

Effects for Erlotinib come from the ADVERSE REACTIONS section of its FDA label; effects for Ostarine come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 12,442 voluntary FDA FAERS reports for Erlotinib that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

How to take them

Some Erlotinib Products Have a Food Rule — Ostarine Should Not Break It

At least one FDA label for a product containing Erlotinib says to take it on an empty stomach. Most supplements — Ostarine included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Erlotinib on its own and move Ostarine to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Erlotinib products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

Recommended Dose – NSCLC The recommended daily dose of erlotinib tablets for NSCLC is 150 mg taken on an empty stomach, i.e., at least one hour before or two hours after the ingestion of food.

From the Dosage and Administration section of the FDA label we read for Erlotinib — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

Everything else you take

See Every Supplement That Interacts With Erlotinib

This page covers Ostarine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Erlotinib page lists 18 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Bilberry (moderate), Coffee Charcoal (moderate), European Mandrake (moderate) and Glucomannan (moderate).

By severity: 1 major · 8 moderate · 9 minor.

From our pharmacist’s overview on the Erlotinib page

“Activated charcoal is the entry I would flag first for anyone taking erlotinib (Tarceva), an oral targeted therapy for certain lung cancers. Charcoal can adsorb the drug in the gut and cut how much reaches the bloodstream, and with a cancer pill, less absorbed means less cancer fought.”

Reviewed by 2 · Jul 18, 2026

Open the Erlotinib 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. Even though Ostarine itself has no known interaction with Erlotinib, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Ostarine and Erlotinib 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
Top half

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

29 days ago today
Medication Erlotinib
Steady interest

#2,520 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Ostarine reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 27, 2026. The Ostarine and Erlotinib records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
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.

Synthetic compound (not from a plant) · Capsules, tablets, liquids, powders sold as research chemicals or 'sports supplements'

An interaction check asks whether these two react with each other — it does not ask whether Ostarine is a good idea for someone in your situation. Here is what our Ostarine record says about it on its own.

Ostarine: dosing

There is no established safe or approved dose of Ostarine, because it is not an approved medicine or a legitimate dietary supplement. Doses used in research studies were given under medical supervision and do not apply to over-the-counter use.We do not recommend using Ostarine. Products sold online may not contain the dose listed on the label and may include other hidden substances.

From our Ostarine monograph — the full record covers uses, side effects and every documented interaction.

Read the full Ostarine monograph & all interactions
Medication

About Erlotinib

What Is Erlotinib Used For?

Brand name: Tarceva

Erlotinib tablets are used to treat metastatic non-small cell lung cancer (NSCLC) in patients whose tumors carry specific gene changes — EGFR exon 19 deletions or exon 21 (L858R) mutations — confirmed by an FDA-approved test. It can be used as a first-line treatment, as maintenance therapy, or after at least one prior chemotherapy has stopped working.

Erlotinib tablets are also used for the first-line treatment of locally advanced, unresectable, or metastatic pancreatic cancer — but only in combination with another chemotherapy drug called gemcitabine. Erlotinib is not recommended alongside platinum-based chemotherapy regimens.

Most-Reported Side Effects for Erlotinib

From FAERS, the FDA’s public side-effect reporting system (12,441 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 1,339 reports
Rash 1,317 reports
Malignant neoplasm progression 890 reports
Fatigue 718 reports
Nausea 696 reports
See full Erlotinib 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
171Minor
2,218No known interaction
440 Moderate 171 Minor 2,218 No interaction
Moderate

440 interactions

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

Minor

171 interactions

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

No interaction 2,218 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 2,218 medications checked with no known interaction — see the full Ostarine list.

See the full Ostarine interactions page
See every supplement checked against Erlotinib, ranked by severity
Evidence & sources

Ostarine References

The 10 references that drive our Ostarine monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Warning Letter: Ironmag Labs 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582464.htm Accessed: November 1, 2017
  2. Warning Letter: Panther Sports Nutrition 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm581630.htm. Accessed: November 1, 2017
  3. Warning Letter: Infantry Labs LLC 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582685.htm. Accessed: November 1, 2017
  4. Dobs AS, Boccia RV, Croot CC, et al. Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. Lancet Oncol 2013;14(4):335-45. PubMed
  5. Dalton JT, Barnette KG, Bohl CE, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II tri
  6. 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
  7. FDA. FDA Warns against using SARMs in body building products. October 2017. Available at: https://www.fda.gov/newsevents/newsroom/fdainbrief/ucm583021.htm.
  8. Bedi H, Hammond C, Sanders D, Yang HM, Yoshida EM. Drug-induced liver injury from enobosarm (ostarine), a selective androgen receptor modulator. ACG Case Rep J 2021;8(1):e00518. PubMed
  9. Kintz P, Gheddar L, Paradis C, et al. Peroxisome Proliferator-Activated Receptor Delta Agonist (PPAR- d) and Selective Androgen Receptor Modulator (SARM) Abuse: Clinical, Analytical and Biological Data in a Case Involving a Poisonous Combination of GW1516
  10. Weinblatt D, Roy S. Drug-Induced Liver Injury Secondary to Enobosarm: A Selective Androgen Receptor Modulator. J Med Cases 2022;13(5):244-248. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Ostarine and Erlotinib Together: Common Questions

Is it safe to take Ostarine with Erlotinib?
We do not list a known interaction between Ostarine and Erlotinib. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Ostarine and Erlotinib have any of the same side effects?
Yes — our sources link each of them separately to 10 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Should I take Ostarine and Erlotinib at the same time of day?
At least one FDA label for a product containing Erlotinib says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Erlotinib on its own and move Ostarine to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.
How was the Ostarine and Erlotinib combination checked?
Interactions in our licensed database are recorded against drug classes. Erlotinib is filed under 2 classifications, and Ostarine has documented interactions with 6 drug classes — none of Erlotinib's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Ostarine interact with any other medications?
Yes. Ostarine has 611 documented drug interactions in our database — Erlotinib is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Erlotinib interact with any supplements?
Yes. Erlotinib has documented interactions with 18 supplements in our database — Ostarine is not one of them. The Erlotinib interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Ostarine monograph Uses, safety profile, and every drug interaction in one place Erlotinib drug information The full plain-English guide to this medication Erlotinib supplement interactions Every supplement checked against Erlotinib, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 10 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Erlotinib and Ostarine?

Our pharmacists answer your medication & supplement questions — free.

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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.