C
Tier
Selective ghrelin-receptor GH secretagogue with a clean profile.
Muscle & Performance
Peptide
WADA Status:
Prohibited at all times (S2)
Human Trial Scoreboard
Completed human RCTs
Count not verified
Largest Human Study
Size not verified
Longest exposure
Duration not verified
Most Recent Trial
Year not verified
Description
Ipamorelin mimics ghrelin, the hormone your stomach releases when empty, and in doing so prompts the pituitary to release growth hormone. It was considered notable for being relatively selective, meaning it triggered less of the cortisol and prolactin response that similar compounds cause. Novo Nordisk investigated it, and it was also explored for a specific hospital problem, the sluggish return of gut function after abdominal surgery. Neither line of work produced an approved medicine. It is often grouped with sermorelin and CJC-1295 despite working through an entirely different receptor: those two imitate the growth hormone releasing signal, while ipamorelin imitates hunger. The gap between raising a hormone level and changing how a body actually looks or performs has never been closed for any compound in this group.
What Are The Claims
Claims made for this compound: Clean GH release with minimal cortisol or prolactin (human PK data); Proposed better sleep, recovery, and body composition; Selectivity is its defining feature
Evidence
The same structural gap as CJC-1295. Small human studies confirm it triggers growth hormone release. There are no outcome trials. The FDA's stated concerns are worth quoting in substance because they are technical rather than political: immunogenicity, meaning the potential for the body to mount an immune response against the peptide, and impurity characterization. Those are manufacturing and safety questions that no vendor certificate of analysis resolves.
Evidence Strength
Preliminary (small human GH-release data)
Caveats
Never approved; a Phase 2 postoperative-ileus program was discontinued after failing endpoints.
Safety
Alternative Measures
Legal Status
US
Not approved
UK
Not approved
EU
Not approved
AU
Not approved
WADA
Prohibited at all times (S2)
Not approved. Placed in FDA Category 2 in September 2023 and removed effective 27 September 2024. The FDA recommended against adding it to the 503A list at the 2024 Pharmacy Compounding Advisory Committee meetings, citing immunogenicity and impurity concerns. WADA-prohibited.
Citations
FDA Pharmacy Compounding Advisory Committee briefing materials: immunogenicity and impurity concerns. | FDA 503A Category 2, September 2023; removed 27 September 2024. | FDA recommended against 503A inclusion, 2024. | WADA Prohibited List.