Growth Hormone
CAS
87616-84-0
Molecular Weight
873
Da
The original growth-hormone-releasing peptide and the template for the entire GHRP family. Well-characterized pharmacology in humans, no therapeutic outcome trials, and the strongest appetite stimulation of any peptide in its class.
Injectable
Intranasal Suitable
Uncertain
Research Compound
GHRP-6 is discussed as the "OG" growth-hormone peptide, respected as the original but often considered superseded by cleaner successors. The single most consistent community theme is hunger: users report a near-immediate, intense appetite spike, which is treated as a feature by those bulking and a dealbreaker by everyone else. It is frequently run alongside a GHRH analog like CJC-1295 to exploit the well-documented synergy. Experienced users flag the cortisol and prolactin bump as the reason they prefer Ipamorelin for cleaner GH release. As with the whole class, the gap to flag is that the robust human data describe GH release, not body-composition or anti-aging outcomes.
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GHRP-6 is a synthetic hexapeptide developed by Cyril Bowers and colleagues in the 1980s. It was the first compound shown to specifically release growth hormone from the pituitary via a then-unknown receptor, later identified as the ghrelin receptor. Every later GH secretagogue peptide, including GHRP-2, Hexarelin, and Ipamorelin, descends from this discovery. The D-amino acids at positions two and five and the C-terminal amide make it resistant to enzymatic breakdown.
GHRP-6 binds the GHS-R1a (ghrelin) receptor on pituitary somatotrophs and in the hypothalamus, stimulating a pulse of growth hormone release that is distinct from, and synergistic with, GHRH. Because it acts on the ghrelin receptor, it also drives strong appetite stimulation and modestly raises cortisol, ACTH, and prolactin, a broader hormonal footprint than its more selective successors. Its GH-releasing effect depends partly on intact hypothalamic GHRH signaling.
Historically used as a research tool and a GH-stimulation test in endocrinology. In the performance and biohacking community it is used off-label to raise GH and IGF-1, support recovery, and stimulate appetite, often paired with a GHRH analog (such as CJC-1295) to exploit the synergy. There are no completed outcome trials for any therapeutic indication.
Human data comes from short pharmacodynamic studies, not long-term safety trials. Reported and expected effects include strong hunger, water retention, tingling or flushing, and transient rises in cortisol and prolactin. Like other GH secretagogues it can raise blood glucose and reduce insulin sensitivity. Long-term safety is uncharacterized, and gray-market product carries the usual contamination and dosing-accuracy concerns. Theoretical caution applies to anyone with a cancer history given GH/IGF-1 signaling.
Supplied as a lyophilized powder for reconstitution and subcutaneous injection; this is the route used in essentially all human research and community use. It is sold as a research chemical "not for human consumption." There is no established oral or intranasal product, though oral administration was explored in early endocrine studies at much higher doses.
GHRP-6 is not approved by the FDA for any use and is not a licensed medicine. It is sold as a research compound labeled "not for human consumption," occupying the same legal gray zone as most peptides in this catalog: purchase and possession are not generally illegal, but marketing or administering it as a drug is not permitted. It is a prohibited substance in competitive sport under WADA.
pubmed.ncbi.nlm.nih.gov/2108187
pubmed.ncbi.nlm.nih.gov/7883854
pubmed.ncbi.nlm.nih.gov/7617137
GHRP-2, Hexarelin, Ipamorelin
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