Overview
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In plain language
Ipamorelin is a lab-made peptide of 5 amino acids that triggers growth hormone release. It was developed in the 1990s by Novo Nordisk.
Researchers liked that it was more selective than similar peptides: it raised growth hormone without raising stress hormones much. It was tested in people to help the gut recover after surgery, but that trial did not show a benefit. It is not FDA-approved.
For students
Ipamorelin (Aib-His-D-2Nal-D-Phe-Lys-NH2, about 712 Da) is a pentapeptide GHS-R1a agonist reported by Raun and colleagues in 1998. Aib is alpha-aminoisobutyric acid, a non-standard amino acid that stabilizes the peptide.
In animal studies, it released growth hormone with potency similar to GHRP-6 but, unlike GHRP-2 and GHRP-6, did not significantly raise ACTH or cortisol even at high doses. That selectivity made it a useful research tool.
For researchers and instructors
Human evidence. Studied clinically by Helsinn for postoperative ileus after bowel surgery, based on ghrelin's prokinetic effects; a Phase 2 trial did not show a significant benefit over placebo.
Pharmacokinetics. Short half-life (about two hours) with dose-proportional GH release.
Regulatory and sport. Not FDA-approved; prohibited by WADA. Often combined in online marketing with CJC-1295, a combination with no published clinical efficacy data.
Molecular identity
- Amino acids
- 5
- Molecular weight
- ~711.9 Da
- Formula
- C₃₈H₄₉N₉O₅
- Sequence
- Aib–His–D-2-Nal–D-Phe–Lys–NH₂
Origin and history
Ipamorelin was developed at Novo Nordisk in Denmark and described in 1998 as “the first selective growth hormone secretagogue.” It came out of the GHRP family pioneered by Cyril Bowers (see GHRP-6), but unlike earlier members it raised growth hormone without also raising cortisol or prolactin.
The company Helsinn later tested it to speed recovery of bowel function after abdominal surgery. A 2014 trial in bowel-resection patients found a trend but no statistically significant benefit, and development stopped. It has never been approved.
Key people
- Kirsten RaunLead author of the 1998 Novo Nordisk paper
Timeline
- 1998
Novo Nordisk publishes ipamorelin as a selective GH secretagogue
- 2008–2011
Helsinn runs trials for postoperative ileus
- 2014
Trial finds no significant benefit; development stops
- Today
Not FDA-approved
See every peptide on one history timeline.
Human evidence
Human pharmacology research exists, but evidence does not establish routine therapeutic effectiveness or long-term safety.
Assess ipamorelin separately from CJC-1295, including sequence, mass and clinical literature.
Explore original publications and distinguish preclinical findings from controlled human evidence.
Safety and regulatory status
See every compound on the regulatory tracker.
Not FDA-approved for therapeutic use.
Product identity, purity, sterility, and endotoxin testing address different risks. This profile is educational and does not provide treatment guidance.
Sources
- Primary scientific source
- Raun et al. 1998, Eur J Endocrinol
- Beck et al. 2014, Int J Colorectal Dis
- ClinicalTrials.gov search: Ipamorelin
Hernandez Gener, E. (2026, November 7). Ipamorelin: molecular data, research history and evidence. VALREXA Biosciences. https://valrexa.com/peptides/ipamorelin.html
APA style · Last reviewed November 7, 2026 · Our editorial standardsLast reviewed November 7, 2026. Trial and regulatory status can change; confirm in the linked registries. This profile is educational and is not medical advice, a treatment recommendation, or dosing or sourcing guidance. Report an error · Corrections policy