GHRP-2

Overview

GHRP-2 is a synthetic hexapeptide growth hormone secretagogue that stimulates the pituitary gland to release growth hormone. It is considered one of the most potent GHRPs available and is used as a GH stimulation test diagnostic in some countries.

Mechanism of Action

GHRP-2 binds to the ghrelin receptor (GHS-R1a) on pituitary somatotroph cells, stimulating growth hormone release. It also suppresses somatostatin, the inhibitory signal for GH release. Unlike GHRP-6, it has minimal impact on cortisol and prolactin at therapeutic doses but does increase appetite modestly through ghrelin-pathway activation.

Research Summary

Clinical studies confirm potent, dose-dependent GH release in healthy subjects and GH-deficient patients. It is approved in Japan as a diagnostic agent (pralmorelin) for GH deficiency. It has been studied for cachexia and age-related GH decline.

Dosing Information

Reported Side Effects

• Increased appetite
• Water retention
• Tingling or numbness in extremities
• Mild cortisol elevation at high doses
• Drowsiness

Research References

• Growth hormone-releasing peptide-2 infusion synchronizes growth hormone, thyrotrophin, and prolactin release (1999)
• GHRP-2 test for the diagnosis of GH deficiency in adults (2001)
• Growth hormone secretagogues: clinical applications (1999)