GHRP-6

What Is GHRP-6?

GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide (His-D-Trp-Ala-Trp-D-Phe-Lys-NH₂) developed by Cyril Bowers and colleagues at Tulane University in the 1980s, as part of the original research program that established synthetic ghrelin-receptor agonists as a distinct class of growth hormone secretagogues. It binds the same receptor studied for Ipamorelin and Hexarelin — GHSR1a — but predates both by well over a decade, and its pharmacological profile is considerably less selective. See its full discovery history.

Research Focus

GHRP-6's defining research characteristic is what it does besides release growth hormone: it produces a pronounced, reliably reproduced increase in appetite (an orexigenic effect far stronger than later secretagogues), and it triggers meaningful off-target increases in cortisol, ACTH, and prolactin alongside GH release. This non-selective profile is precisely what later research programs set out to eliminate — see our Ipamorelin page and its discovery history for how Novo Nordisk's chemists used GHRP-6 as the pharmacological starting point for a more selective successor. See our GHRH & Growth Hormone research overview for how GHRP-6 fits alongside KYIN's stocked GH-axis peptides, or how GHRP-2, Hexarelin, and Sermorelin compare as other non-stocked compounds in this category.

Clinical & Preclinical Trial Data

GHRP-6 has a decades-long human research record dating to its original characterization by Bowers and colleagues (Endocrinology, 1984), which established it as a potent, reliably reproducible GH secretagogue in both animal and early human studies. Subsequent human research through the 1980s and 1990s consistently confirmed its non-selective hormonal profile — robust GH release accompanied by measurable cortisol, ACTH, and prolactin elevation — and its pronounced appetite-stimulating effect, properties that made it a widely used pharmacological research tool even as it was never developed into an approved drug.

GHRP-6's most lasting scientific contribution came indirectly: its receptor-binding activity was central to the 1996 cloning of the growth hormone secretagogue receptor (GHS-R1a) by Howard and colleagues (Science), which in turn enabled the 1999 discovery of ghrelin itself by Kojima and colleagues (Nature) as that receptor's endogenous ligand. GHRP-6 is not FDA-approved and has not been developed into a marketed drug.

Explore the Full GHRP-6 Research Cluster

Every angle of GHRP-6 research in one place:

• Mechanism of Action — a non-selective ghrelin receptor agonist
• Discovery & Research History — the 1980s secretagogue that predated Ipamorelin
• GHRP-6 vs Ipamorelin — the original secretagogue versus its selectivity-engineered successor
• Certificate of Analysis Guide — how to read GHRP-6's purity testing
• Product & Pricing

Availability

GHRP-6 is part of KYIN Peptides' standard catalogue — see the product page for pricing, or contact us to order.