GHRP-2

GHRP-2 is a synthetic hexapeptide growth hormone (GH) secretagogue. It binds and activates the growth hormone secretagogue receptor (GHS-R1a) — the same receptor targeted by the endogenous hormone ghrelin — in the pituitary and hypothalamus. Activation stimulates pulsatile release of GH from pituitary somatotrophs, working partly by amplifying the action of hypothalamic GH-releasing hormone (GHRH) and by suppressing somatostatin tone; consequently it raises downstream IGF-1. Because it acts on the ghrelin receptor, GHRP-2 also stimulates appetite and can transiently raise cortisol and prolactin. Unlike GHRH analogues, it does not require an intact GHRH signal to work, and it is orally and intranasally active, which underlies its historical use as a provocative diagnostic agent.

Human data on GHRP-2 come mainly from its role as a GH-stimulation (provocative) test rather than as a therapy. Laferrère et al. (JCEM, 2005) showed that infused GHRP-2 increased food intake by ~36% in healthy men, confirming ghrelin-like appetite effects. Asakura et al. (J Pediatr Endocrinol Metab, 2010) validated GHRP-2 as a safe, rapid provocative test for GH deficiency in children. In Japan the compound is approved as pralmorelin for diagnostic GH-stimulation testing — the only regulatory approval any GH secretagogue holds. Mechanistic and preclinical work (e.g., Zeng et al., Peptides, 2014, on ghrelin-receptor/opioid antinociception) further maps GHS-R1a signalling, but there are no large trials supporting GHRP-2 for muscle building, anti-aging, or performance.

Educational overview only — no dosing instructions in the public hub.

GHRP-2 raises GH and IGF-1 and can stimulate appetite and transiently increase cortisol and prolactin. Elevated GH/IGF-1 can cause water retention, joint pain, carpal-tunnel-type symptoms, and insulin resistance/impaired glucose tolerance; sustained supraphysiologic GH/IGF-1 carries theoretical concerns for tissue overgrowth and tumour promotion. Long-term human safety outside short diagnostic use is not established. For gray-market material, sourcing and purity are major practical risks. GHRP-2 is a prohibited GH secretagogue in sport at all times.

Outside the Japanese diagnostic product (pralmorelin), no pharmaceutical-grade GHRP-2 is available in most markets. Any research material should carry a recent third-party Certificate of Analysis covering identity, purity (HPLC), quantification, and mass spectrometry. Content here reflects the peptide as characterised in the clinical and preclinical literature, not gray-market material of unverified composition.

Approved only in Japan (as pralmorelin) for diagnostic GH-stimulation testing; elsewhere it is research-use-only and not approved for general human use. Supplying it for human consumption outside its approved diagnostic context is unlawful in most jurisdictions. As a GH secretagogue it is on the WADA Prohibited List (class S2) and is banned in sport at all times, in and out of competition.