MK-677
Ibutamoren — an orally active growth-hormone secretagogue studied for sustained GH and IGF-1 elevation.
Overview
MK-677 (Ibutamoren) is an orally active growth-hormone secretagogue, distinct from injectable peptides in that it’s a small molecule rather than a peptide chain. It was originally developed in the 1990s by pharmaceutical researchers investigating treatments for growth-hormone deficiency and age-related muscle loss.
Mechanism of Action
MK-677 acts as an agonist at the ghrelin receptor (GHSR), stimulating pulsatile growth-hormone release from the pituitary gland in a manner similar to peptide secretagogues like Ipamorelin, but with oral bioavailability and a substantially longer half-life — a distinction that has made it a common comparison point in growth-hormone-axis research.
Cited Research
Original receptor-agonist pharmacology
Characterized MK-677’s activity at the ghrelin receptor as an orally bioavailable secretagogue.
GH/IGF-1 elevation in older adults
Studied sustained growth-hormone and IGF-1 elevation in aging-population clinical research.
Body-composition research
Examined effects on lean mass and body composition over extended administration periods.
Sleep-quality research
Explored as a secondary endpoint in several growth-hormone-axis clinical trials.
This is a summary, not an exhaustive review. Search the primary literature yourself: MK-677 on PubMed →
Safety & Handling
MK-677 should be handled only by qualified personnel in a laboratory setting, stored per its Certificate of Analysis, and kept in a cool, dry place away from light. It is not evaluated or approved by the FDA for any human or veterinary use.
Frequently Asked Questions
Is MK-677 a peptide?
No — unlike most compounds in this library, MK-677 is a small molecule, not a peptide chain. It’s grouped with growth-hormone-axis research compounds because it acts on the same ghrelin-receptor pathway as peptides like Ipamorelin.
Is MK-677 legal to purchase?
It’s legal to sell and purchase as a research chemical for laboratory use in the U.S. It is not approved by the FDA as a drug or supplement for human consumption.
How should MK-677 capsules be stored?
Keep in a cool, dry place away from direct light and moisture, as indicated on the Certificate of Analysis.
Is this page medical advice?
No. This page summarizes published literature for research and educational context only. It does not recommend a dose, protocol, or use in humans or animals outside a laboratory setting.
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