What it is
MK-677 (ibutamoren) is an orally active ghrelin-receptor agonist. It has been studied for its effect on growth hormone and IGF-I levels.
What the research says
- A two-year randomized, placebo-controlled trial in 65 healthy adults aged 60 to 81 reported that MK-677 increased growth hormone and IGF-I levels [1].
- The same trial reported adverse effects. On average, fasting blood glucose rose by about 5 mg/dL and insulin sensitivity decreased. Body weight and cortisol levels also rose. The most frequent side effects were increased appetite, which subsided within a few months, and transient, mild lower-extremity edema and muscle pain [1].
- FDA's compounding safety page cites a potential congestive heart failure signal: a randomized trial of ibutamoren in people recovering from hip fracture 'was terminated early due to a potential safety signal of congestive heart failure' [2].
Regulatory status
MK-677 is investigational. It is not FDA approved for any use, and compounded versions are not FDA approved. Where prescribed, compounded versions are prepared by state-licensed 503A compounding pharmacies.
Safety and side effects
Two safety signals matter most. First, the trial above reported higher fasting glucose and lower insulin sensitivity [1]. Second, FDA cites a potential congestive heart failure signal [2]. A licensed healthcare provider should review your history, medications and labs, including heart and blood-sugar history, carefully before deciding anything.
Is it right for you?
Only a licensed healthcare provider can decide whether any treatment is appropriate for you.
Frequently asked questions
What did the main trial of MK-677 find?
In healthy adults aged 60 to 81 it raised growth hormone and IGF-I levels. The trial also reported adverse effects, including higher fasting glucose, lower insulin sensitivity, weight gain, higher cortisol, increased appetite, and transient mild edema and muscle pain [1].
What are the main safety concerns with MK-677?
FDA cites a potential congestive heart failure signal from a terminated trial [2], and the older-adult trial reported effects on blood glucose and insulin sensitivity [1].
Is MK-677 approved by FDA?
No. MK-677 is not FDA approved and is investigational. Compounded versions are not FDA approved.
Do I need a prescription for MK-677?
Yes. Prescription only, requires evaluation by a licensed provider. A provider decides whether it is appropriate for you.
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):601-611 (PubMed 18981485). https://pubmed.ncbi.nlm.nih.gov/18981485/
- FDA: Certain bulk drug substances for use in compounding that may present significant safety risks. https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
MK-677 content on this page is for education. Compounded medications are not FDA approved. Prescription only, requires evaluation by a licensed provider. Educational content only, not medical advice.