Ipamorelin and Muscle Gain: What Has Been Studied

What the research covers

No published human trial was found that tested ipamorelin for muscle gain. The human studies looked at GH levels in healthy men and at bowel recovery after surgery. Ipamorelin is a lab-made peptide, five amino acids long, that triggers the release of growth hormone (GH). It acts on the ghrelin receptor.

In a dosing study, healthy men got a 15-minute infusion at one of five doses, eight men per dose. GH rose in a single peak at about 40 minutes, then fell to very low levels at every dose. The drug had a half-life of 2 hours. A phase 2 trial gave ipamorelin or placebo by IV to adults after bowel surgery. The dose was 0.03 mg per kilogram twice a day, for up to 7 days. Of 117 patients enrolled, 114 were analysed. Ipamorelin was well tolerated but did no better than placebo.

In a rodent (rat) study, a steroid drug made the animals lose body protein. Ipamorelin at 0.5 mg per kilogram a day for 7 days offset this loss. In another rodent (rat) study, 8-month-old females got a steroid for 3 months, with or without ipamorelin. The ipamorelin dose was 100 micrograms per kilogram under the skin, three times a day. It offset the steroid-driven loss of calf muscle strength and bone formation. A third rodent (rat) study gave adult females shots for 15 days. Bone growth in length and weight gain both rose, more so at higher doses. In a rodent (mouse) study, ipamorelin raised body weight by 15% within 2 weeks. Those animals were growth-hormone-deficient (lit/lit) or carried one copy of that gene change (+/lit). It also raised the share of body fat.

A PubMed search on 27 September 2026 found no human trial of ipamorelin for muscle, lean mass or strength. No study giving ipamorelin with CJC-1295 was found.

Sources

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