Ipamorelin is a selective growth hormone secretagogue receptor (GHSR) agonist — a synthetic ghrelin mimetic that stimulates GH release with high selectivity. Unlike older GH secretagogues, ipamorelin does not significantly stimulate cortisol, prolactin, or ACTH release in research models, making it one of the most commonly studied selective GH secretagogues in preclinical literature. It is almost always studied alongside CJC-1295.
Selectivity advantage
Ipamorelin's defining research characteristic is its selectivity. Earlier GHSR agonists (GHRP-2, GHRP-6) produced significant cortisol and prolactin responses in animal models, complicating interpretation of GH-specific effects. Ipamorelin's high selectivity for GHSR allows researchers to study GH secretagogue effects more cleanly. This selectivity makes it the dominant choice in GH-axis research protocols.
Ipamorelin + CJC-1295
The FIT Stack (or CJC-1295 + Ipamorelin combination) is the most popular growth hormone research pairing. CJC-1295 stimulates GHRH receptors to amplify GH pulse size; ipamorelin acts through a completely different receptor (GHSR) to trigger the actual GH release. The two mechanisms are complementary and synergistic in animal models, making the combination a standard research tool for GH-axis investigation.
Dosing and format
Ipamorelin is available as lyophilized powder in 2mg and 5mg vials. It has a short half-life requiring administration in pulses in animal model protocols. COA requirements are standard: third-party HPLC ≥98% purity, mass spec identity (MW 711.87 g/mol), and lot number traceability.
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