Ipamorelin
Human RCTNNC 26-0161 · Ipamorelin acetate
Highest available evidence among curated papers: Human RCT (as of 2026-06-04).
Chemical & identity
- Molecular formula
- C38H49N9O5
- Molecular weight
- 711.9 g/mol · PubChem
- PubChem CID
- 9831659 · PubChem
- SMILES
- CC(C)(C(=O)N[C@@H](CC1=CN=CN1)C(=O)N[C@H](CC2=CC3=CC=CC=C3C=C2)C(=O)N[C@H](CC4=CC=CC=C4)C(=O)N[C@@H](CCCCN)C(=O)N)N
- InChIKey
- NEHWBYHLYZGBNO-BVEPWEIPSA-N
- ChEMBL ID
- CHEMBL58547 · ChEMBL
- Category
- GH secretagogue/GHRH
Chemical/structural fields are auto-pulled and source-linked. ChEMBL data: ChEMBL_36, CC BY-SA 3.0.
Mechanism (curated)
Selective growth-hormone secretagogue; agonist at the ghrelin/GHS-R1a receptor that stimulates pulsatile pituitary GH release without substantially affecting other pituitary hormones.
Pharmacology & handling
- Half-life
- Approximately 2 hours.
Research
Gouda M, Ganesh CB · Animal reproduction science · 2024 · Animal study
This animal study examined how ipamorelin acetate (IPA), a ghrelin agonist, affects the reproductive axis in tilapia fish (Oreochromis mossambicus). Fish treated with 5 or 30 µg IPA for 21 days showed dose-dependent increases in food intake and elevated numbers of primary and secondary spermatocytes and early spermatids compared to controls. At the 30 µg dose, late spermatids, lobule area, and lumen area were also significantly increased. IPA treatment increased serum concentrations of luteinizing hormone and 11-ketotestosterone in a dose-dependent manner and elevated androgen receptor protein expression at the 30 µg dose, though GnRH-immunoreactive fibres showed no significant differences. The authors conclude that ghrelin agonism may enhance germ cell development during meiosis-I via stimulation of 11-KT and androgen receptors at the testicular level and LH at the pituitary level.
Beck DE et al. · International journal of colorectal disease · 2014 · RCT
This was a phase 2, multicenter, double-blind, randomized controlled trial in 114 adults undergoing bowel resection surgery. Patients received intravenous ipamorelin (0.03 mg/kg twice daily) or placebo from postoperative day 1 through day 7 or hospital discharge to evaluate safety and efficacy for postoperative ileus. The primary endpoint was time to tolerance of a standardized solid meal; median times were 25.3 hours for ipamorelin versus 32.6 hours for placebo (p = 0.15), showing no statistically significant difference. Ipamorelin was well tolerated with adverse event rates of 87.5% in the ipamorelin group and 94.8% in placebo. The authors concluded there were no significant differences between ipamorelin and placebo in efficacy measures.
Efficacy of ipamorelin, a novel ghrelin mimetic, in a rodent model of postoperative ileus.
Animal-onlyVenkova K et al. · The Journal of pharmacology and experimental therapeutics · 2009 · Animal study
This animal study investigated ipamorelin, a ghrelin receptor agonist, in a rodent model of postoperative ileus (POI) induced by laparotomy and intestinal manipulation. Male rats received either a single dose or repetitive doses of ipamorelin (0.01–1 mg/kg), GHRP-6 (20 µg/kg), or vehicle via intravenous infusion. A single dose of ipamorelin (1 mg/kg) decreased time to first bowel movement but did not affect fecal output, food intake, or body weight at 48 hours post-surgery. Repetitive dosing of ipamorelin (0.1–1 mg/kg) significantly increased cumulative fecal output, food intake, and body weight gain. The authors conclude that intravenous ipamorelin infusions may ameliorate POI symptoms in patients, though this conclusion is not directly tested in the provided abstract.
Johansen PB et al. · Xenobiotica; the fate of foreign compounds in biological systems · 1998 · Animal study
This study evaluated the pharmacokinetics of ipamorelin and other peptidyl growth hormone secretagogues in male rats following intravenous and intranasal administration. After intravenous injection, ipamorelin showed a 5-fold lower systemic plasma clearance than GHRP-6, was primarily excreted in urine, and was moderately resistant to metabolism with 60–80% recovery as intact peptide. Following intranasal application, ipamorelin had a bioavailability of approximately 20%, lower than other tested peptides but demonstrating feasibility of nasal delivery. The study suggests the nasal route is promising for systemic delivery of this class of peptidyl growth hormone secretagogues.
Lu Z et al. · Physiology & behavior · 2024 · Animal study
This animal study investigated whether the growth hormone secretagogue receptor 1a agonists anamorelin and ipamorelin can alleviate cisplatin-induced weight loss and feeding inhibition in ferrets. Both compounds inhibited cisplatin-induced weight loss during the delayed phase (48–72 h) by approximately 24% when given intraperitoneally, but neither affected cisplatin-induced emesis via this route. Anamorelin administered intracerebroventricularly reduced acute cisplatin-induced emesis by 60% and improved food and water consumption by 20–40% during the acute phase, also reducing weight loss during the delayed phase by ~23%. The study suggests that central nervous system penetration is important for anamorelin's anti-emetic effects, and both compounds act as ghrelin mimetics to mitigate cisplatin-induced adverse effects in this ferret model.
Svensson J et al. · The Journal of endocrinology · 2000 · Animal study
This animal study investigated whether two GH secretagogues, ipamorelin (IPA) and GHRP-6, increase bone mineral content (BMC) in young adult female Sprague-Dawley rats. Rats received IPA (0.5 mg/kg/day), GHRP-6 (0.5 mg/kg/day), GH (3.5 mg/kg/day), or vehicle via subcutaneous osmotic minipumps for 12 weeks, with bone measurements by DXA in vivo and pQCT and Archimedes' principle in vitro. All treatments increased total tibial and vertebral BMC and tibial area BMD compared with controls; however, when corrected for body weight gain, total BMC ratio and volumetric bone mineral density were unchanged. The increases in cortical and total BMC were due to increased bone growth and dimensions rather than changes in volumetric mineral density.
Greenwood-Van Meerveld B et al. · Journal of experimental pharmacology · 2012 · Animal study
This rodent study investigated whether ipamorelin, a ghrelin receptor agonist, improves gastric emptying in a postoperative ileus model induced by abdominal surgery and intestinal manipulation. Adult male rats received ipamorelin (0.014–0.14 µmol/kg intravenously) or vehicle control after surgery, with gastric emptying measured by radiolabeled meal retention. Ipamorelin at 0.014 µmol/kg significantly accelerated gastric emptying compared to vehicle-treated surgical controls (52% vs 78% retention), approaching levels in non-surgical controls (44% retention). In isolated gastric tissue, ipamorelin reversed the surgery-induced inhibition of smooth muscle contractility evoked by acetylcholine and electrical stimulation. The authors conclude ipamorelin accelerates gastric emptying through ghrelin receptor-mediated activation of cholinergic excitatory neurons.
Gobburu JV et al. · Pharmaceutical research · 1999 · Other
A dose escalation study in eight healthy male volunteers per dose level examined the pharmacokinetics and pharmacodynamics of ipamorelin, a growth hormone-releasing peptide, across five infusion rates (4.21 to 140.45 nmol/kg over 15 minutes). Ipamorelin showed dose-proportional kinetics with a 2-hour half-life, clearance of 0.078 L/h/kg, and volume of distribution of 0.22 L/kg. The peptide induced a single episode of GH release peaking at 0.67 hours, with an estimated SC50 of 214 nmol/L for half-maximal stimulation and maximum GH production rate of 694 mIU/L/h. A pharmacokinetic-pharmacodynamic model was developed to characterize ipamorelin disposition and GH responses, with inter-individual variability in PD parameters exceeding that of PK parameters.
Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats.
Animal-onlyJohansen PB et al. · Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society · 1999 · Animal study
Ipamorelin is a synthetic pentapeptide with growth hormone-releasing properties. In this animal study, adult female rats received subcutaneous injections of ipamorelin at doses of 0, 18, 90, or 450 micrograms per day for 15 days. Ipamorelin dose-dependently increased longitudinal bone growth rate in the proximal tibia and body weight gain. The treatment did not significantly affect total IGF-I levels, IGF-binding proteins, serum bone markers, or osteoclast numbers. The authors note that clinical studies in children with growth retardation would be needed to establish a therapeutic role.
Raun K et al. · European journal of endocrinology · 1998 · Other
This study describes the development and pharmacology of ipamorelin, a pentapeptide growth hormone secretagogue. In vitro testing with rat pituitary cells showed ipamorelin released GH with potency and efficacy similar to GHRP-6. In anesthetized rats and conscious swine, ipamorelin stimulated GH release with potency and efficacy comparable to GHRP-6. Notably, unlike GHRP-6 and GHRP-2, ipamorelin did not significantly elevate ACTH or cortisol levels, even at doses 200-fold higher than the ED50 for GH release. The authors conclude ipamorelin is the first GHRP-receptor agonist with selectivity for GH release similar to GHRH, making it a candidate for clinical development.
Andersen NB et al. · Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society · 2001 · Animal study
This animal study investigated whether ipamorelin, a growth hormone secretagogue, could counteract the catabolic effects of glucocorticoids on muscle and bone in adult female rats. Rats received either glucocorticoid (methylprednisolone), ipamorelin, or both in combination for 3 months. Combined treatment with glucocorticoid and ipamorelin significantly increased muscle tetanic tension and increased periosteal bone formation rate approximately four-fold compared to glucocorticoid alone. The study concludes that ipamorelin counteracted the glucocorticoid-induced decreases in muscle strength and bone formation.
Mechanism of ipamorelin-evoked insulin release from the pancreas of normal and diabetic rats.
Animal-onlyAdeghate E, Ponery AS · Neuro endocrinology letters · 2004 · Animal study
This study examined ipamorelin (IPA), a pentapeptide with growth hormone-releasing activity, on insulin secretion from pancreatic tissue fragments in normal and streptozotocin-induced diabetic rats. Ipamorelin evoked significant increases in insulin secretion in both normal and diabetic rat pancreatic tissue. Pharmacological inhibitors of calcium channels (diltiazem), adrenergic receptors (propranolol, yohimbine), and cholinergic pathways (atropine) significantly reduced IPA-evoked insulin secretion, with atropine showing differential effects between normal and diabetic tissues. The authors conclude that ipamorelin stimulates insulin release through calcium channel and adrenergic receptor pathways.
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Regulatory status
- FDA approved
- No
- WADA prohibited
- Yes
- Compounding status
- Not an approved drug; clinical development discontinued. Sold as a research chemical.
- Notes
- Not FDA-approved; clinical development discontinued. Prohibited in sport under WADA (growth-hormone secretagogue), as of 2026-06-04.
Legal/regulatory status varies by jurisdiction and changes over time — accurate as of last review (2026-06-04).
Data sources: Curated IDs (PubChem/UniProt/ChEMBL) + Europe PMC + ClinicalTrials.gov (2026-06-04).
Last reviewed 2026-06-04