⚖ Head-to-Head · GHRH vs Secretagogue

Sermorelin vs MK-677

Mechanism, half-life, dosing & research status compared side-by-side.

Sermorelin
Growth Hormone
Compounding Only
Growth HormoneAnti-agingRecoverySleep
Sermorelin is a synthetic analog of the first 29 amino acids of endogenous GHRH, retaining full biological activity at the GHRH receptor. It was FDA approved (Geref) for GH deficiency in children from 1997 until its volu…
Full Sermorelin profile →
MK-677
Growth Hormone & IGF
Not Approved
Growth HormoneOralNon-PeptideWADA ProhibitedPhase II
MK-677 (ibutamoren) is an orally active, non-peptide ghrelin receptor agonist (GHS-R1a) that stimulates GH release from the pituitary without requiring injection. It was developed by Merck and advanced through Phase II t…
Full MK-677 profile →
Technical Specs Comparison
MetricSermorelinMK-677
Research Status Extensively Studied Phase II (Discontinued)
Molecular Weight 3,357.9 Da 624.8 Da
Half-Life ~10–20 min ~24 hours
Peak Time ~30–60 min -
Typical Dose 200–500 µg 10–25 mg
Frequency Once daily (bedtime) Once daily
Route Subcutaneous Oral
Amino Acids 29 -
WADA Status Prohibited Prohibited
FDA Status Compounding Only Not Approved
Stack Compatibility & Key Differences
Both are active research compounds. See individual pages for full protocol data.
Frequently Asked Questions
What is the difference between Sermorelin and MK-677?
Sermorelin: Sermorelin is a synthetic analog of the first 29 amino acids of endogenous GHRH, retaining full biological activity at the GHRH receptor. It was FDA approved (Geref) for GH deficiency in children from 1997 until its volu… MK-677: MK-677 (ibutamoren) is an orally active, non-peptide ghrelin receptor agonist (GHS-R1a) that stimulates GH release from the pituitary without requiring injection. It was developed by Merck and advanced through Phase II t…
Can you stack Sermorelin and MK-677?
Both are active research compounds. See individual pages for full protocol data.
Which has a longer half-life, Sermorelin or MK-677?
Sermorelin half-life: ~10–20 min. MK-677 half-life: ~24 hours.
Verified Scientific Data
All specifications on this page are sourced from peer-reviewed literature and primary research. Half-life values, dosing ranges, and mechanism data are cross-referenced against published studies. Last audited 2026-06-07.
Peer-reviewed sources Audit timestamp: 2026-06-07 Data version: ASCEND Wiki 2026
Data sourced from ASCEND Wiki · Sermorelin profile · MK-677 profile · All comparisons
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