This page describes published research and public regulatory records. It is not medical advice. SoluneFit does not sell, supply, or recommend any compound. The SoluneFit app includes a private, on-device tracker for people who want a record of what they and their clinician have already decided — the app neither suggests compounds nor doses.
Also known as: ibutamoren, ibutamoren mesylate, MK-0677.
Regulatory status
Not approved. FDA placed ibutamoren mesylate in category 2 (significant safety risks, potential congestive heart failure) for 503B (29 Dec 2022) and 503A (29 Sep 2023) compounding [4]. FDA warning letters treat products containing it as unapproved new drugs and state it is excluded from the dietary-supplement definition (e.g. Dec 2025) [5]. WADA-prohibited at all times (S2.2.4) [6].
What it is
Non-peptide oral GH secretagogue (small-molecule ghrelin receptor agonist).
A once-daily pill developed by Merck that mimics ghrelin and raises growth hormone and IGF-1 into young-adult ranges. It was tested in older adults, obesity, hip-fracture recovery and Alzheimer disease but never approved; one trial was stopped early for a heart-failure signal.
What the published research shows
Several human RCTs: 65 healthy adults aged 60-81 for up to 2 years, 123 hip-fracture patients (stopped early), 563 Alzheimer patients for 12 months, plus short studies; raised GH/IGF-1 and lean mass but no functional or cognitive benefit.
Published human studies and reports (these describe trial populations, not SoluneFit claims):
- Healthy older adults (Nass 2008, Ann Intern Med): 25 mg orally once daily vs placebo for 12 months (2-year modified crossover) in 65 adults aged 60-81. Fat-free mass +1.1 kg vs -0.5 kg on placebo; body weight +2.7 kg vs +0.8 kg; no change in visceral fat, strength or function; fasting glucose +0.3 mmol/L (5 mg/dL) with reduced insulin sensitivity; cortisol up 47 nmol/L.
- Hip-fracture recovery (Adunsky 2011, phase IIb): 25 mg/day (n = 62) vs placebo (n = 61) in elderly hip-fracture patients for up to 24 weeks: IGF-1 +51.4 ng/mL and gait speed slightly better, but most functional measures unchanged. The trial was terminated early for a safety signal of congestive heart failure in a limited number of patients.
- Healthy elderly, dose-finding (Chapman 1996): 2, 10 or 25 mg once daily for 14 and 28 days in 32 subjects aged 64-81: 25 mg raised mean 24-h GH 97 % and IGF-1 from 141 to 265 µg/L at 4 weeks; fasting glucose rose from 5.4 to 6.8 mmol/L.
- Alzheimer disease (Sevigny 2008): 25 mg daily vs placebo for 12 months in 563 patients with mild-to-moderate AD: IGF-1 rose 72.9 % but there was no effect on any cognitive or functional scale.
Mechanism, as reported
Activates the ghrelin (GH secretagogue) receptor, amplifying the body's own pulsatile GH release, which in turn raises IGF-1. It also increases appetite and lowers insulin sensitivity.
Practical record
- Studied routes: oral.
- Typical supply: Sold as capsules, tablets or liquids on the research/supplement market; no licensed product exists.
- Reconstitution: Oral compound; not reconstituted.
Safety signals on record
- Reported adverse events: In trials: increased appetite (fading over months), mild transient leg swelling (oedema) and muscle pain, weight gain, higher fasting glucose and reduced insulin sensitivity, small rises in cortisol and prolactin.
- Contraindications: None established (no label). FDA's stated concern is congestive heart failure in certain patients, from the halted hip-fracture trial.
- Interactions: None documented.
- Notes: Its effects on glucose matter for anyone with prediabetes or diabetes. Banned in sport at all times. Plasma half-life was not found in a primary source opened for this entry (UNVERIFIED); once-daily dosing in trials kept IGF-1 raised.
Sources
- Nass R et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med 2008;149(9):601-11 (2008)
- Adunsky A et al. MK-0677 (ibutamoren mesylate) for the treatment of patients recovering from hip fracture: a multicenter, randomized, placebo-controlled phase IIb study. Arch Gerontol Geriatr 2011;53(2):183-9 (2011)
- Chapman IM et al. Stimulation of the GH-IGF-I axis by daily oral administration of a GH secretogogue (MK-677) in healthy elderly subjects. J Clin Endocrinol Metab 1996;81(12):4249-57 (1996)
- FDA. Certain bulk drug substances for use in compounding that may present significant safety risks (category 2 list; content current as of 04/22/2026) (2026)
- FDA Warning Letter to Musclepower Enterprise Ltd. dba Monster King and GE Labs (MARCS-CMS 719339), 12 Dec 2025 (2025)
- World Anti-Doping Agency. The 2026 Prohibited List (S2.2.4 Growth hormone releasing factors) (2026)
- Sevigny JJ et al. Growth hormone secretagogue MK-677: no clinical effect on AD progression in a randomized trial. Neurology 2008;71(21):1702-8 (2008)
General wellness education, not medical advice. Unapproved compounds have no established dosing, purity standard, or safety profile.