MK-677
Overview
MK-677 (Ibutamoren) is a non-peptide, orally bioavailable ghrelin mimetic and GH secretagogue. Despite being frequently categorized with peptides, it is a spiropiperidine compound — not a peptide itself. It binds the ghrelin receptor (GHSR-1a), stimulating GH and IGF-1 release without suppressing cortisol. Oral administration distinguishes it from most peptide secretagogues. In Phase II clinical trials (e.g., PMID 9467534), doses of 10–25 mg/day were studied for GH deficiency and muscle wasting. Known effects in trials include increased appetite, water retention, and potential elevation of fasting glucose. Not approved for clinical use. Consult a licensed physician before use.
Dosage
25 mg · Any time · Can take on empty stomach
What Experts Say
“"MK-677 can more than double circulating cortisol levels — that is a significant concern for long-term use"”
MK-677 (Ibutamoren) is an oral GH secretagogue that mimics ghrelin to stimulate GH and IGF-1 release. Huberman groups it in a cautious category due to significant side effects: elevated cortisol (can more than double circulating cortisol), elevated prolactin causing libido suppression and fluid retention, increased hunger and anxiety. It is the only non-injectable option in this class, which is its primary advantage.
“"MK-677 is as strong as injectable GH peptides, but it is much cheaper, does not need refrigeration, and does not need to be injected"”
Derek covers MK-677 as the only orally bioavailable GH secretagogue — no injections needed, no refrigeration, no PCT required. Typical doses range from 12.5–25 mg/day. Must be cycled due to diminishing returns and long-term blood glucose elevation risk (insulin resistance). Side effects include increased hunger (via ghrelin), water retention, and early lethargy. Derek rates it cautiously positive for those seeking GH benefits without needles, but emphasizes monitoring blood glucose and not running it continuously.
Scientific Sources
- MK-677, an orally active growth hormone secretagogue, reverses diet-induced catabolism. (J Clin Endocrinol Metab, 1998 Feb)
- Effects of oral ibutamoren mesylate on GH secretion. (Clin Pharmacol Ther, 2001 Jul)
- MK-0677 for treatment of patients recovering from hip fracture. (Arch Gerontol Geriatr, 2011 Sep-Oct)
- Phase NA | COMPLETED | GH Secretagogue MK-0677 Effect on IGF-1 Levels in ESRD
- Phase PHASE2 | COMPLETED | Impact of Ibutamoren on Nonalcoholic Fatty Liver Disease
- pubmed_ncbi_api
- pubmed_ncbi_api
- PubChem Compound 178024
Frequently Asked Questions
What is MK-677 used for?
MK-677 (Ibutamoren) is a non-peptide, orally bioavailable ghrelin mimetic and GH secretagogue.
What is the recommended dosage for MK-677?
25 mg. Any time. Can take on empty stomach.
Does MK-677 interact with other supplements?
No verified interactions found for MK-677 in our database yet.
When is the best time to take MK-677?
Any time. Can take on empty stomach.
Is MK-677 safe to combine with other supplements?
Always check interactions before combining supplements. Use VitalStack to verify your full stack for free.
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