hormoneNot FDA-approvedResearch chemicalEnobosarm (MK-2866/ostarine) has never received FDA approval for any indication and is not a lawful dietary supplement ingredientThe FDA has issued public warnings about SARM products, including ostarine, sold online as research chemicals or supplements
MK-2866 SublingualBenefits, Dosage & Interactions
Also known as: Ostarine liquid
MK-2866, commonly known as Ostarine, is a selective androgen receptor modulator (SARM) that has been investigated for its potential to affect muscle and bone tissue. Research on MK-2866 Sublingual focuses on muscle and strength and bone and joint health. Dose, response, and interaction risk vary by individual, so use should be reviewed with a clinician.
Researched by DoseRoutine R&D TeamReviewed for accuracy by Nicholas Alexander, RSELast updated
Evidence: Strong — 2 human randomized trials published.
Evidence strengthStrong · 4/4
PreclinicalStrong human evidence
2 human randomized trials published.
Plasma half-life
Not established
Default unit
mg
What published protocols report
Ranges documented in the literature, shown for reference. DoseRoutine does not recommend an amount — your prescriber or the product label sets the dose.
- Reported amounts
- Cited phase 2 trials studied oral enobosarm at 1-3 mg/day (cachexia trial) and 18 mg/day (breast cancer trial); none of the cited trials evaluated a sublingual formulation[1][2]
Reported for MK-2866 Sublingual in the cited sources. Published ranges are not dosing advice.
References & evidence
Documents the MK-2866 Sublingual entry is written from. Each number matches an inline marker above.
- [1]Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trialDobs AS, Boccia RV, Croot CC, Gabrail NY, Dalton JT, Hancock ML, Johnston MA, Steiner MS · The Lancet Oncology · 2013 · Peer-reviewed · PMID 23499390
- [2]Activity and safety of enobosarm, a novel, oral, selective androgen receptor modulator, in androgen receptor-positive, oestrogen receptor-positive, and HER2-negative advanced breast cancer (Study G200802): a randomised, open-label, multicentre, multinational, parallel design, phase 2 trialPalmieri C, Linden H, Birrell SN, Wheelwright S, Lim E, Schwartzberg LS, Dwyer AR, Hickey TE, Rugo HS, Cobb P, O'Shaughnessy JA, Johnston S, Brufsky A, Tilley WD, Overmoyer B · The Lancet Oncology · 2024 · Peer-reviewed · PMID 38342115
- [3]Nonsteroidal selective androgen receptor modulator Ostarine in cancer cachexiaZilbermint MF, Dobs AS · Future Oncology · 2009 · Peer-reviewed · PMID 19852734
How to track MK-2866 Sublingual doses
MK-2866 Sublingual is tracked as a protocol rather than a single reminder: a vial with a concentration, a schedule that may be titrated or cycled, and a rotation of injection sites. Here is the record that keeps all three consistent.
- 1
Record the vial and concentration
Log the vial strength and the volume of bacteriostatic water you added so MK-2866 Sublingual is stored as a concentration rather than a guess. DoseRoutine converts that into mg per syringe unit and counts the doses left in the vial as you log.
- 2
Set the schedule, not just a reminder
Enter the dose in mg and the frequency. Cycled protocols get a start and end date so the history stays accurate when MK-2866 Sublingual comes out of the routine.
- 3
Rotate and log the injection site
Pick the site at the moment you log the dose. The site map shows what you used last and how recently, which is the part that drifts fastest when two compounds run on different frequencies.
- 4
Log adherence, not intentions
Mark each dose taken, skipped or delayed as it happens. Weeks of honest logs are what make an adherence rate or a trend line meaningful; retrospective guessing is not.
- 5
Review against outcomes
Review MK-2866 Sublingual alongside your logged metrics and any relevant blood work every few weeks before changing the dose, so the change is a response to data rather than to a good or bad day.
What to log each time
- Dose in mg and the syringe units it worked out to
- Vial: reconstitution date, concentration, doses remaining
- Injection site and time
- Any side effects in the 24 h after the dose
What is MK-2866 Sublingual studied for?
What is MK-2866 Sublingual?
MK-2866, commonly known as Ostarine, is a selective androgen receptor modulator (SARM) that has been investigated for its potential to affect muscle and bone tissue. It is distinct from anabolic steroids in its proposed mechanism of action, aiming to selectively target androgen receptors in certain tissues while minimizing effects on other organs. Although often discussed in contexts related to muscle enhancement, MK-2866 is not approved for medical use in humans by the U.S. Food and Drug Administration (FDA) or other major regulatory bodies. It has primarily been studied in preclinical and clinical research settings, often for conditions involving muscle wasting or bone loss. The sublingual form refers to its administration method, where the liquid is absorbed under the tongue. (Source: PubChem, FDA Website).
What does the research say about MK-2866 Sublingual?
Tap a section to expand.
MK-2866 functions by selectively binding to androgen receptors (ARs) in the body. Unlike traditional anabolic steroids, which bind to ARs throughout the body, SARMs like Ostarine are hypothesized to exhibit tissue-selective activation. This selectivity is intended to lead to anabolic effects, such as increased protein synthesis in muscle and bone cells, while theoretically reducing androgenic side effects in other tissues like the prostate or skin. By binding to ARs, MK-2866 can modulate the expression of genes involved in muscle growth and maintenance, as well as bone density. This selective modulation is the basis for its potential therapeutic applications in conditions characterized by muscle atrophy or osteoporosis. (Source: DrugBank, NIH PubMed research).
Research into MK-2866 has explored several potential benefits, primarily related to muscle and bone health. Studies have investigated its ability to increase lean muscle mass and improve physical function, particularly in individuals experiencing muscle wasting due to illness or age. For example, some clinical trials have observed improvements in total lean body mass and stair climb power in elderly subjects. Additionally, MK-2866 has been studied for its potential to improve bone mineral density. These effects are attributed to its selective activation of androgen receptors in muscle and bone. However, these are research findings, and MK-2866 is not an approved medication for these purposes. (Source: NIH clinical trials database, peer-reviewed scientific literature).
The evidence for MK-2866's effects comes primarily from preclinical studies and early-phase human clinical trials. A significant amount of research has focused on its efficacy in models of muscle wasting and osteoporosis. For instance, studies have shown that MK-2866 can increase lean body mass and muscle strength in healthy older men and postmenopausal women. Other research has indicated its potential to improve physical performance and reduce fat mass. These studies often compare MK-2866 to placebo, observing statistically significant differences in outcomes such as lean mass gains. However, the long-term safety and efficacy profile in humans are still under investigation, and larger, more comprehensive studies are generally needed before definitive conclusions regarding its medical utility can be drawn. The FDA has not approved MK-2866 for any human medical use, and it is listed as a prohibited substance by anti-doping agencies due to its performance-enhancing potential. (Source: Cochrane Library reviews of SARMs, U.S. Anti-Doping Agency).
While MK-2866 aims for tissue selectivity, it is not without potential side effects. Reported side effects in research settings have included transient decreases in levels of high-density lipoprotein (HDL, or 'good' cholesterol), particularly with higher doses. Some users have also anecdotally reported mild gastrointestinal disturbances, headaches, or suppression of natural testosterone production, although the extent of suppression is generally considered less severe than that associated with anabolic steroids. The long-term safety profile of MK-2866 is not yet fully established due to its status as an investigational compound. As an unapproved substance, there are also risks associated with product quality and purity in the unregulated market. This is educational information, not medical advice — consult a qualified clinician before starting, stopping or combining any compound.
MK-2866 is not approved for human consumption by regulatory bodies like the FDA. Its use carries inherent risks, including the potential for uncharacterized long-term side effects and interactions. Individuals using MK-2866 should be aware that products sold online may not contain the advertised contents, or may be contaminated with other substances. There is also a risk of liver toxicity, although studies generally suggest it may be lower than with some oral anabolic steroids. Furthermore, even with its purported selective action, it can still suppress natural hormone production, potentially leading to symptoms of low testosterone after discontinuation, possibly requiring post-cycle therapy. Athletes should note that MK-2866 is explicitly prohibited by major sports organizations. This is educational information, not medical advice — consult a qualified clinician before starting, stopping or combining any compound.
Due to its investigational status and potential hormonal effects, MK-2866 is generally contraindicated in certain populations. This includes pregnant or breastfeeding women, as its effects on fetal development or infant health are unknown. Individuals with pre-existing liver conditions, cardiovascular disease, or hormonal imbalances should avoid MK-2866 due to the potential for exacerbating these conditions. Those with a history of prostate issues, including prostate cancer, should also refrain from use due to the androgenic nature of the compound, despite its alleged selectivity. As it has not been approved for any medical indication, specific contraindications based on comprehensive clinical trials are still being elucidated, but caution is paramount for anyone considering its use. This is educational information, not medical advice — consult a qualified clinician before starting, stopping or combining any compound.
Due to the investigational and unapproved nature of MK-2866, specific interactions with other drugs or supplements are not well-established through formal studies. However, caution is advised when combining it with any other compound that may affect liver function, such as certain medications that are metabolized by the liver, or other compounds known to have hepatotoxic potential. Combining it with other compounds that impact the endocrine system or hormone levels, including other SARMs, prohormones, or anabolic steroids, could exacerbate potential side effects, increase the risk of hormonal imbalance, or lead to unpredictable outcomes. As MK-2866 can affect lipid profiles, combining it with medications for cholesterol management should be done with extreme caution, and only under medical supervision. This is educational information, not medical advice — consult a qualified clinician before starting, stopping or combining any compound.
In research settings, MK-2866 has typically been administered once daily due to its approximately 24-hour half-life. For sublingual liquid formulations, the compound is held under the tongue for absorption before swallowing. The preference for administration with or without food is generally considered flexible, with no strong evidence suggesting one is superior over the other for absorption or efficacy. However, individual product instructions or research protocols should always be followed if available. The duration of use in studies has varied, but often involves cycles of several weeks, followed by a break. This is based on research protocols and not a recommendation for use. (Source: published pharmacokinetic studies).
What interacts with MK-2866 Sublingual?
| Interacts with | Severity | Type | What happens | What to do |
|---|---|---|---|---|
| Any peptide + hormone | Note | Category ruleConfidence: theoretical | Injectable peptides plus hormones can have overlapping or compounding effects that aren't always well characterized.Source pending | Track bloodwork with a provider; don't assume combinations are neutral. |
Frequently asked questions about MK-2866 Sublingual
MK-2866 Sublingual is a hormone. It is also known as Ostarine liquid. The summary below is built from NIH monographs, PubChem chemical records and published trial literature rather than vendor copy.
MK-2866 Sublingual is commonly discussed in the context of supporting muscle and bone-joint. Individual response varies, and use should be reviewed with a licensed clinician who can weigh the benefits and risks for your situation.
For MK-2866 Sublingual, it is typically taken null. Always follow the specific dose your clinician or the product label prescribes.
MK-2866 Sublingual carries potential side effects and drug interactions, documented in NIH, Mayo Clinic, and FDA label sources. Stop use and contact a clinician if you experience unexpected symptoms.
Interaction risk for MK-2866 Sublingual comes from the rest of the stack: other hormones, prescription medicines, hormone therapy and peptides. Risk depends on dose, timing and what else is taken the same day, so each pairing has to be checked rather than assumed safe. The free checker at https://doseroutine.com/interaction-checker covers MK-2866 Sublingual with no sign-up.
There is no single answer for MK-2866 Sublingual plus TRT. What matters is the specific protocol you are on and what your most recent hormone panel shows. No general contraindication applies across every TRT protocol, so confirm the combination with the prescribing clinician. See the free TRT interaction reference: https://doseroutine.com/trt-supplement-interactions
Pairing MK-2866 Sublingual with peptides has to be assessed one peptide at a time, because GLP-1 agonists, secretagogues, healing peptides and melanocortins do not share an interaction profile. Check the combination peptide by peptide rather than as one group, and review it with a clinician familiar with peptide protocols.
Published frequency for MK-2866 Sublingual varies by protocol and formulation, so the label or prescription is what sets it. Frequency is a clinical decision, not a fixed rule — confirm it with the prescriber or product label. Comparison of apps that keep a schedule like this: https://doseroutine.com/best-dose-tracking-apps
The effect of a missed dose of MK-2866 Sublingual depends on the protocol and formulation you are on. Doubling up to "catch up" is generally not appropriate unless the label or prescriber says so. Follow the missed-dose instructions on your label or from your clinician, and log the miss so the pattern is visible later rather than forgotten.
For MK-2866 Sublingual the useful record is the dose, the time it was actually taken, and what else was taken in the same window. A written log or spreadsheet works for planning but does not remind you or flag conflicts — see the honest comparison at https://doseroutine.com/vs/spreadsheet and the wider roundup at https://doseroutine.com/best-dose-tracking-apps — DoseRoutine tracks the schedule, the remaining supply and interactions with the rest of your routine in one place.
Sources cited on this page
Specific documents referenced by the numbered markers above. Each number matches the marker in the text.
- WADA Prohibited List(opens in a new tab)World Anti-Doping Agency · wada-ama.org/en/prohibited-list
Verify at
Publisher search links for MK-2866 Sublingual. These are places to check the information — they are not citations, so they are not numbered.
- PubChem(publisher search, opens in a new tab)National Center for Biotechnology Information · publisher search
- DrugBank(publisher search, opens in a new tab)DrugBank Online · publisher search
- PubMed literature search(publisher search, opens in a new tab)National Library of Medicine · publisher search
- FDA-approved labeling (DailyMed)(publisher search, opens in a new tab)U.S. Food and Drug Administration · publisher search
- ClinicalTrials.gov(publisher search, opens in a new tab)U.S. National Library of Medicine · publisher search
- Cochrane Library(publisher search, opens in a new tab)Cochrane · publisher search
DoseRoutine compiles summaries from publicly available scientific and regulatory references. Always verify important decisions with a licensed clinician. How we source and review this information.
What is the short answer on MK-2866 Sublingual?
Plain-text summary, safe to quote verbatim:
MK-2866, commonly known as Ostarine, is a selective androgen receptor modulator (SARM) that has been investigated for its potential to affect muscle and bone tissue. Research on MK-2866 Sublingual focuses on muscle and strength and bone and joint health. Dose, response, and interaction risk vary by individual, so use should be reviewed with a clinician.
Source: DoseRoutine — https://doseroutine.com/library/mk-2866-sublingual
Cite this page
Using this in an article, AI answer, or research note? Please attribute:
DoseRoutine. (2026). MK-2866 Sublingual — Overview, Benefits & Side Effects. Retrieved from https://doseroutine.com/library/mk-2866-sublingual
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Which goals is MK-2866 Sublingual used for?
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