Ipamorelin
Growth-hormone secretagogue (ghrelin mimetic)
Also known as: NNC 26-0161
A selective growth-hormone secretagogue that stimulates GH release with minimal effect on cortisol or prolactin. Human evidence is limited to early-phase work.
Selectivity is well characterized preclinically, but robust long-term human efficacy trials are lacking.
Mostly small, open-label, or observational human data.
Intended use
Used off-label/research for GH support, body composition, recovery, and sleep quality.
Mechanism of action
Selective agonist of the ghrelin/GH-secretagogue receptor, triggering pulsatile growth-hormone release from the pituitary.
Reported benefits
Selective GH release
Raises growth hormone without large spikes in cortisol or prolactin in early studies.
Recovery & body composition
Anecdotally used to support lean mass and recovery.
Sleep quality
Users report improved deep-sleep; mechanism plausible via GH pulsatility.
Risks & side effects
Water retention
low riskGH elevation can cause fluid retention and joint discomfort.
Insulin sensitivity
moderate riskSustained GH elevation may impair glucose tolerance.
Unregulated supply
high riskPredominantly sold as a research chemical.
Research & citations
Studies are ordered by design strength. Dots indicate the rigor of each study type — meta-analyses and double-blind RCTs rank highest, case reports and in vitro work lowest.
- GH secretagogues and body composition
Class effects on GH/IGF-1 with limited long-term outcome data.
Growth Hormone & IGF Research · 2008 · n = Small
Open-label / Cohort - Ipamorelin, the first selective growth hormone secretagogue
Potent, selective GH release without ACTH/cortisol increase.
European Journal of Endocrinology · 1998 · n = Swine / rats
Animal / Preclinical
Legal status by region
Regulatory status varies widely and changes often. Verify against current local law before acting.
| Region | Status | Notes |
|---|---|---|
| United States | Research only | Not FDA-approved; on the 503A compounding review list. |
| European Union | Research only | No human marketing authorization. |
| Global (sport) | Banned | Prohibited by WADA at all times. |
Sourcing & prescribing
Where a compound can legally be obtained, and who is able to prescribe it.
- Gray area
Research-chemical vendors
Sold 'for research use only'.
- Gray area
Anti-aging / hormone clinics
Some clinics offer it off-label where permitted.
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