Peptide Graded

Ipamorelin

Does Ipamorelin work?

Not properly: animal or lab studies, or small uncontrolled human reports. small hormone tests, and a failed trial in 117 bowel surgery patients.

CAnimal and cell studiesNot approvedas of 2026-10-27

For the anti-aging and body-composition use ipamorelin is sold for, no human trial exists. The human data are a 40-volunteer dose-escalation pharmacokinetic study showing a single growth hormone pulse, a 114-patient randomised phase 2 trial in post-operative ileus that found no benefit, and a comparative hormone study of related peptides. The selectivity claim comes from rats and swine. 462

Gobburu and colleagues infused ipamorelin at five rising doses. Each dose level had eight healthy men. The peptide had a half-life of about two hours. It produced a single growth hormone peak at about 40 minutes. The level then fell steadily back to baseline. There was no second pulse at any dose. 4

One trial had a clinical outcome measure. It randomised 117 adults having bowel resection to ipamorelin or placebo by vein for up to seven days. The analysis covered 114 of them. Median time to eating a solid meal was 25.3 hours with ipamorelin against 32.6 hours with placebo. This difference was not statistically significant. No secondary measure favoured the drug. The compound was well tolerated. 6

Evidence checklist

  • Randomised controlled trial Phase 2 ileus trial, but not the sold use
  • Human study over 100 people Phase 2 ileus trial, 114 analysed
  • More than one research group Novo Nordisk studies; no independent work
  • Clinical outcomes, not surrogate markers Ileus trial negative; no body-composition data
  • Human safety data beyond case reports Seven-day surgery trial; long-term unknown

Read the full Ipamorelin page

More on Ipamorelin

Citations

  1. Cleveland Clinic: ghrelin overview my.clevelandclinic.org
  2. Raun 1998, European Journal of Endocrinology: ipamorelin, the first selective growth hormone secretagogue pubmed.ncbi.nlm.nih.gov
  3. Growth Hormone and IGF Research 2001: ipamorelin study doi.org
  4. Gobburu 1999, Pharmaceutical Research: pharmacokinetic-pharmacodynamic modeling of ipamorelin in human volunteers pubmed.ncbi.nlm.nih.gov
  5. Venkova 2009, Journal of Pharmacology and Experimental Therapeutics: ipamorelin in a rat model of post-operative ileus doi.org
  6. Beck 2014, International Journal of Colorectal Disease: randomised proof-of-concept study of ipamorelin for post-operative ileus pubmed.ncbi.nlm.nih.gov
  7. FDA: certain bulk drug substances for use in compounding may present significant safety risks fda.gov
  8. Ghigo 1997, European Journal of Endocrinology: growth hormone-releasing peptides, review pubmed.ncbi.nlm.nih.gov
  9. Arvat 1997, Peptides: effects of GHRP-2 and hexarelin on GH, prolactin, ACTH and cortisol in man pubmed.ncbi.nlm.nih.gov
  10. FDA: bulk drug substances nominated for use in compounding under section 503A, category list fda.gov
  11. Thomas 2012, Journal of Chromatography A: determination of prohibited small peptides in urine for sports drug testing pubmed.ncbi.nlm.nih.gov

Reference information only, not medical advice. Drawn from the Ipamorelin article, fact-checked against the cited sources. No dosing anywhere on this site.