Ipamorelin vs Sermorelin

Ipamorelin binds to the ghrelin receptor (GHSR-1a) and stimulates dose-dependent GH release with a clean hormonal profile. Unlike GHRP-6 or hexarelin, it does not significantly stimulate appetite-related pathways or cortisol secretion at standard research doses. This selectivity makes it a frequently studied peptide for protocols where hormonal side-effect profiles are a consideration.

Ipamorelin is a selective growth hormone secretagogue and ghrelin receptor agonist. It stimulates pulsatile GH release from the anterior pituitary with high selectivity — producing minimal effect on cortisol, prolactin, or ACTH compared to earlier GHRPs. It is commonly researched for its role in supporting body composition, recovery, and lean mass maintenance.

Sermorelin is a synthetic analogue of the first 29 amino acids of endogenous growth hormone-releasing hormone (GHRH). It binds to GHRH receptors on pituitary somatotrophs, stimulating pulsatile GH secretion in a physiological pattern that preserves the natural hypothalamic-pituitary feedback axis — contrasting with direct GH administration. Downstream IGF-1 elevation mediates many of its body composition, tissue-repair, and sleep quality effects.

Sermorelin is a GHRH analogue used to stimulate endogenous growth hormone production. It is one of the most widely prescribed peptides in the anti-aging and functional medicine space, valued for preserving the natural pituitary feedback axis while supporting body composition, sleep quality, and tissue repair. Compounded formulations are available in the US through 503A pharmacies.