Overview
GHRP-2 (Pralmorelin) is a synthetic hexapeptide ghrelin receptor agonist and potent growth hormone secretagogue. Approved in Japan as a diagnostic agent for GH deficiency, it is the most selective of the first-generation GHRPs, producing strong GH release with less appetite stimulation than GHRP-6 and lower cortisol/prolactin elevation than other peptides in its class.
Mechanism of action
GHRP-2 acts as a selective agonist at the ghrelin receptor (GHSR-1a) in the pituitary and hypothalamus. Binding triggers calcium mobilization and protein kinase C activation, resulting in pulsatile GH release from somatotroph cells. Simultaneously, GHRP-2 suppresses somatostatin tone, which normally inhibits GH secretion, thereby amplifying net GH output. It also activates hypothalamic neuropeptide Y (NPY) neurons, contributing to mild appetite stimulation — though this effect is significantly less pronounced than with GHRP-6. At standard doses GHRP-2 produces modest cortisol and prolactin elevation, which some users manage by pairing it with a GHRH analog. Its short plasma half-life (~15 minutes) requires multiple daily injections to maintain elevated GH pulsatility.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| GH secretion and body composition | subcutaneous | 100–300 mcg | 2–3 times daily | Users commonly inject 100–300 mcg per dose on an empty stomach, 3 times daily (morning, pre-workout, and pre-sleep). Often paired with a GHRH analog (CJC-1295, Mod-GRF 1-29) for synergistic effect. |
| diagnostic GH stimulation test (clinical use) | intravenous | 100–100 mcg | single dose | Japanese PMDA-approved diagnostic protocol: 100 mcg IV bolus, GH measured at 30, 60, and 90 minutes. Peak GH >16 ng/mL (children) or >9 ng/mL (adults) rules out deficiency. |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Approved by Japan's PMDA in 2004 as a diagnostic agent for GH deficiency assessment; a single 100 mcg IV bolus is the established clinical test dose. Preclinical and Phase 2 studies demonstrate robust GH and IGF-1 elevation in healthy adults and GH-deficient patients. Limited published data on long-term anabolic or body composition outcomes. Community use is widespread for muscle building, recovery, and anti-aging, but evidence is largely from user-reported protocols rather than controlled clinical trials.
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with GHRP-2 for synergistic effects.
Legal status
GHRP-2 was placed on the FDA Category 2 bulk drug substance list in September 2023, banning compounding pharmacy preparation in the US. Industry analysis as of February 2026 suggests GHRP-2 is among the peptides expected to remain on Category 2 (due to cortisol and prolactin elevation concerns) rather than returning to compounding-eligible status. No formal FDA update published as of April 2026. Approved as a diagnostic agent in Japan.
Where to get it
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