Scientific Reference
Ipamorelin
Evidence profile: Human Phase 2 evidence
Ipamorelin is a selective growth hormone releasing peptide (GHRP) that stimulates endogenous growth hormone (GH) secretion via activation of ghrelin (GHS-R1a) receptors in the pituitary. It is characterized by a highly selective profile, producing GH release without significant stimulation of cortisol or prolactin. This selectivity distinguishes it from earlier GHRPs, making it a preferred compound in research focused on body composition, recovery, sleep, and anti-aging. Its ability to preserve physiological GH pulsatility while minimizing off-target endocrine effects has positioned it as a core peptide in GH optimization protocols.
Mechanism of Action
Ipamorelin binds selectively to ghrelin receptors (GHS-R1a) in the pituitary, triggering pulsatile release of growth hormone. This activation leads to downstream increases in IGF-1 while preserving natural feedback mechanisms. Unlike earlier GHRPs, it does not significantly stimulate ACTH, cortisol, or prolactin pathways, resulting in a cleaner endocrine profile.
Molecular Information
- Type: Growth hormone secretagogue (GHRP)
- Length: 5 amino acids
- Molecular weight: 711.9 g/mol
- Molecular formula: C38H49N9O5
- CAS: 170851-70-4
Published Research
Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients
Beck DE et al. · International journal of colorectal disease · 2014 · Clinical
PMID 25331030 — View on PubMedPharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers
Gobburu JV et al. · Pharmaceutical research · 1999 · Clinical
PMID 10496658 — View on PubMed