One of the original GHRPs — potent GH stimulation with strong appetite-increasing effects.
GHRP-6 is a hexapeptide and one of the original synthetic growth hormone releasing peptides. It was among the first GHRPs studied extensively in human subjects. Like other GHRPs, it acts on the ghrelin receptor to stimulate GH release from the pituitary gland.
GHRP-6 is notable for producing very strong appetite stimulation — significantly more than ipamorelin or GHRP-2. This is due to its potent ghrelin-mimetic effects. For patients seeking to increase caloric intake (e.g., recovery from illness, muscle building), this appetite effect may be desirable. For others, it can be problematic.
GHRP-6 also raises cortisol and prolactin more than ipamorelin. For these reasons, most modern protocols prefer ipamorelin when a 'cleaner' GH secretagogue is desired. GHRP-6 is largely of historical interest in the peptide field, though it remains available.
Decades of research establish GHRP-6's pharmacological profile clearly. Studies in GH-deficient children and adults show effective GH stimulation. The appetite-stimulating effects have been studied separately in cachexia (muscle wasting) research.
Some research suggests gastroprotective effects — similar to BPC-157 — mediated through ghrelin receptor activation in the gut. This is an area of ongoing investigation.
📚 Key Reference: PMID: 2912225 (original GHRP-6 research)
Strong appetite stimulation is the most significant concern for many patients — can lead to significant caloric intake increases. Cortisol elevation. Water retention. Lethargy. GH-related side effects with excessive use. Consult your provider.
NOT FDA-approved. Research use only. Available through compounding pharmacies.