Growth hormone secretagogues explained: GHRH vs GHRP

"Growth hormone secretagogue" is an umbrella term for compounds that prompt the pituitary gland to release its own growth hormone. Within that umbrella sit two distinct families — GHRH analogues and GHRPs — and understanding the difference is the key to reading this whole area of research.

The two families

GHRH analogues, such as tesamorelin and CJC-1295, mimic the body's natural growth-hormone-releasing hormone. GHRPs (growth-hormone-releasing peptides), such as ipamorelin, are a separate class. Both aim to stimulate the pituitary, but they do so through different receptors, which is the central distinction researchers work with.

Two receptors, two doors

GHRH analogues act on the GHRH receptor — the pituitary's natural input for this signal. GHRPs act on the growth-hormone secretagogue receptor, also known as the ghrelin receptor. Because these are two separate doors into the same system, each family produces its own pattern of activity in laboratory models, and each is studied for what it reveals about the axis.

Why they are studied together

A recurring theme in the published research literature is that the two families can act in a complementary way. When a GHRH analogue and a GHRP are examined together in study models, researchers observe how the two signals combine at the pituitary. This is why the compounds in this category are so often discussed as pairs rather than in isolation.

From powder to bench

Every secretagogue in this catalogue — GHRH analogue or GHRP — is supplied as a lyophilised powder and reconstituted with bacteriostatic water before use; our reconstitution guide and the on-site reconstitution simulator cover the method. Each batch ships with a certificate of analysis issued within six months of sale, so identity and purity are documented before work begins.