What is Ipamorelin?
Ipamorelin is a synthetic pentapeptide growth hormone secretagogue. This page covers its formal identifiers, its receptor target, and the clinical and preclinical research that has studied it.
Ipamorelin is a synthetic pentapeptide growth hormone secretagogue (GHS) and a selective agonist of the growth hormone secretagogue receptor 1a (GHS-R1a), also known as the ghrelin receptor. It is one of the compounds grouped in the literature among growth hormone secretagogues, alongside GHRP-2, GHRP-6, and hexarelin [3]. The evidence block for this page does not supply a sequence, molecular formula, or molecular weight for ipamorelin, so none are stated here.
The research literature centres on the GH-IGF-1 axis and on GHS-R1a signalling. Ipamorelin is discussed as a peptide intended to modulate the growth hormone–insulin-like growth factor-1 axis, a category that also includes GHRH analogues such as sermorelin, tesamorelin, and CJC-1295 with and without DAC, and the GH fragment AOD9604 [3].
Research Studies
Ipamorelin and post-operative gastrointestinal recovery after bowel resection
A registered clinical trial was designed to test whether post-operative administration of Ipamorelin reduces the time to recovery of gastrointestinal function in patients who have undergone partial small and/or large bowel resection [1]. The stated expectation in the trial record is a reduction in time to recovery of GI function in that surgical population [1]. The record describes the study as an evaluation of safety and efficacy compared with placebo [1].
Ipamorelin and post-operative ileus
A separate registered trial was designed to determine whether ipamorelin is safe and effective in the management of post-operative ileus [2]. As with the bowel resection study, the population is surgical patients, and the outcome of interest is the resolution of a post-operative gastrointestinal motility problem [2]. Both trials therefore place ipamorelin's clinical research history in a perioperative GI context rather than in a healthy-volunteer or athletic context [1][2].
Ipamorelin and GHS-R1a agonism in cisplatin-treated ferrets
Preclinical work examined whether ghrelin mimetics, specifically anamorelin and ipamorelin, alleviate weight loss and inhibition of feeding during the acute and delayed phases of cisplatin-induced emesis in ferrets [9]. The same study investigated the potential of anamorelin to inhibit electrically field stimulation-induced contractions of isolated tissue [9]. This is an animal model of chemotherapy-induced emesis and weight loss; the findings are not human findings and are reported here as animal-model observations [9].
Ipamorelin acetate and the hypothalamic-pituitary-testicular axis in a cichlid fish
A study in the tilapia Oreochromis mossambicus examined the impact of ipamorelin acetate, described as a ghrelin agonist, on the reproductive axis [10]. The work was framed around the prediction that ghrelin, a peptide found in the brain and gut, plays a role in the control of multiple physiological systems in fish [10]. This is a non-mammalian, non-human model, and the results pertain to that species [10].
Ipamorelin and the GH-IGF-1 axis in performance-enhancing peptide literature
Review coverage of performance-enhancing drugs marketed as research compounds places ipamorelin within the growth hormone secretagogue class, alongside GHRP-2, GHRP-6, and hexarelin [3]. That literature describes these peptides as unregulated agents intended to modulate the GH-IGF-1 axis and notes that they appear in online self-administration protocols encountered in clinical practice [3]. The framing is descriptive of the market and the class, not a report of efficacy in any population [3].
Ipamorelin and the gray-market research peptide supply chain
An evaluation of research-grade peptides marketed directly to consumers assessed purity, measured abundance, and endotoxin burden using a large publicly available independent testing dataset, and compared cost against compounded and FDA-approved alternatives [4]. The study describes a rapidly expanding, largely unregulated gray market selling preparations directly to consumers for self-administration, with purported benefits including accelerated musculoskeletal injury recovery, muscle hypertrophy, fat loss, and athletic performance enhancement [4]. Ipamorelin sits within the peptide category that market serves; the study's findings concern the supply chain and product quality of that category rather than ipamorelin-specific outcomes [4].
Ipamorelin and the broader therapeutic peptide literature in aging and sports medicine
Narrative review work on therapeutic peptides in gerontology covers mechanisms, clinical applications, evidence base, and safety profiles of peptides with demonstrated or potential applications in healthy aging and age-related conditions, targeting hallmarks that include metabolic dysfunction, telomere attrition, tissue repair impairment, and hormonal decline [5]. Separately, reviews of approved and unapproved peptide therapies for musculoskeletal injuries and athletic performance describe peptides as short amino acid chains occupying a pharmacological niche between small-molecule drugs and large proteins, and note a parallel gray market of unapproved compounds operating largely outside regulatory oversight [6][7]. These reviews situate ipamorelin within a class-level discussion; they do not report ipamorelin-specific human efficacy data in the material available here [5][6][7].
Ipamorelin and evidence quality in injectable peptide sports medicine reviews
Structured review work on injectable peptides in sports medicine notes that clinical adoption has outpaced high-quality evidence and regulatory consensus, and sets out to summarise contemporary human and translational evidence [12]. Related review work on peptide supplements in sports medicine describes rapid market growth driven by marketing claims of enhanced performance and accelerated recovery from musculoskeletal injury, and notes that these products are often perceived as low risk despite the absence of efficacy or safety data [11]. Both are reference-level sources for this page: they describe the state of the evidence for the peptide category, not ipamorelin-specific trial results [11][12].
Comparison of evidence contexts for ipamorelin
The table below summarises the model or population in which each cited body of work was conducted. It is a map of the evidence, not a ranking of it.
| Evidence source | Model or population | What was examined |
|---|---|---|
| NCT01280344 [1] | Patients after partial small and/or large bowel resection | Time to recovery of GI function versus placebo |
| NCT00672074 [2] | Patients with post-operative ileus | Safety and effectiveness in management of post-operative ileus |
| Ferret cisplatin model [9] | Ferrets | Cisplatin-induced weight loss, feeding inhibition, and isolated tissue contractility |
| Cichlid fish study [10] | Oreochromis mossambicus | Hypothalamic-pituitary-testicular axis |
| PED landscape review [3] | Clinical practice and online self-administration protocols | Class placement of ipamorelin among growth hormone secretagogues |
| Gray-market peptide evaluation [4] | Consumer-marketed research peptides | Purity, measured abundance, endotoxin burden, cost |
If you are reading this for personal health reasons
This material is sold for laboratory research only. We do not provide dosing or medical guidance, and nothing on this page is medical advice. Anyone considering a compound for themselves should speak to a licensed clinician.
Sources
- [1] Safety and Efficacy of Ipamorelin Compared to Placebo for the Recovery of Gastrointestinal Function — https://clinicaltrials.gov/study/NCT01280344
- [2] Safety and Efficacy of Ipamorelin for Management of Post-Operative Ileus — https://clinicaltrials.gov/study/NCT00672074
- [3] The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis — https://europepmc.org/article/PMC/PMC13322892
- [4] Evaluation of Research Grade Peptides Marketed Directly to Consumers Reveals Extensive Variability in Purity and Measured Abundance — https://doi.org/10.20944/preprints202604.1748.v1
- [5] Therapeutic peptides in gerontology: mechanisms and applications for healthy aging — https://europepmc.org/article/PMC/PMC13095733
- [6] Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance — https://doi.org/10.20944/preprints202512.1011.v3
- [7] Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance — https://doi.org/10.20944/preprints202512.1011.v1
- [9] The growth hormone secretagogue receptor 1a agonists, anamorelin and ipamorelin, inhibit cisplatin-induced weight loss in ferrets — https://pubmed.ncbi.nlm.nih.gov/39043357/
- [10] The influence of ghrelin agonist ipamorelin acetate on the hypothalamic-pituitary-testicular axis in a cichlid fish, Oreochromis mossambicus — https://pubmed.ncbi.nlm.nih.gov/38996787/
- [11] Peptide Supplements and Their Therapeutic Applications in Sports Medicine — https://pubmed.ncbi.nlm.nih.gov/42578445/
- [12] Injectable Peptides in Sports Medicine: A Structured Narrative Review of Evidence, Safety, and Antidoping Implications — https://pubmed.ncbi.nlm.nih.gov/42160466/