What Is GHRP-6?
GHRP-6 (growth-hormone-releasing peptide-6) is a synthetic hexapeptide that binds the ghrelin/GH-secretagogue receptor to release growth hormone, and is notable for also strongly stimulating appetite. It was one of the first GH-releasing peptides discovered and acts through a protein-kinase-C-dependent pathway on pituitary somatotrophs 1Reference 1Growth hormone releasing peptide (GHRP-6) stimulates phosphatidylinositol turnover in human pituitary somatotroph cells — human cell studyView study →. It is used mainly as a research tool; in the “research peptide” market it is taken to raise GH and increase hunger. It is not an approved medicine or dietary supplement.
Evidence
GHRP-6 stimulates GH secretion from human pituitary cells via a PKC/Ca²⁺-dependent, cAMP-independent mechanism 1Reference 1Growth hormone releasing peptide (GHRP-6) stimulates phosphatidylinositol turnover in human pituitary somatotroph cells — human cell studyView study →, and in animal models it activates the brain’s appetite centres (arcuate nucleus and related hypothalamic regions), consistent with its well-known orexigenic (hunger-inducing) effect 2Reference 2AnimalAcute central ghrelin and GH secretagogues induce feeding and activate brain appetite centres — in vivo (rat) studyView study →. Most of the mechanistic and appetite data are preclinical or from cell systems, and robust controlled human outcome trials (for muscle, fat, or clinical appetite/cachexia endpoints) were not verified in this quick pass. Claims that GHRP-6 delivers reliable body-composition or performance benefits in humans are not supported by a verified clinical outcome trial here.
Dosage & Safety
There is no established supplement dose for GHRP-6; online regimens are not derived from controlled human efficacy trials, and this page makes no dosing recommendation. GHRP-6 is not FDA-approved as a drug or dietary supplement and is prohibited in sport (WADA). It reliably increases hunger and can raise cortisol/prolactin. Human long-term safety, drug interactions, and pregnancy/lactation safety are not established / not assessed in this pass. This entry is informational only and not an endorsement of use.
References
- Lania A, et al. (1995). Growth hormone releasing peptide (GHRP-6) stimulates phosphatidylinositol turnover in human pituitary somatotroph cells — human cell study. J Clin Endocrinol Metab. https://pubmed.ncbi.nlm.nih.gov/7772238/
- Lawrence CB, et al. (2002). Acute central ghrelin and GH secretagogues induce feeding and activate brain appetite centres — in vivo (rat) study. Endocrinology. https://pubmed.ncbi.nlm.nih.gov/11751604/