Also known as Pralmorelin · KP-102 · GPA-748
Second-generation synthetic GHRP; a potent ghrelin-receptor agonist approved in Japan as a diagnostic for GH deficiency.
Research refreshed
GHRP-2 (pralmorelin) is a synthetic hexapeptide growth-hormone secretagogue that activates the GHS-R1a (ghrelin) receptor on pituitary somatotrophs. More potent than its predecessor GHRP-6, it is one of the very few GHRPs to reach regulatory approval anywhere — used in Japan as a single-injection diagnostic test of pituitary GH reserve.
GHRP-2 is a second-generation growth-hormone-releasing peptide, developed after GHRP-6 as researchers tuned the original hexapeptide for greater potency. Like the rest of the family it activates the ghrelin receptor (GHS-R1a) on pituitary somatotrophs, driving a discrete pulse of endogenous growth hormone rather than supplying GH directly.
It occupies an unusual place among research GHRPs: it is actually an approved drug in Japan (as pralmorelin), where a single injection is used to test whether the pituitary can release GH — a diagnostic for growth-hormone deficiency. It is not FDA-approved in the United States. Compared with GHRP-6 it releases more GH per dose and provokes noticeably less of GHRP-6’s hallmark hunger, though it is less selective than ipamorelin and can transiently raise cortisol and prolactin.
GHS-R1a (ghrelin receptor) agonism → pulsatile GH release.
Behind every vial of GHRP-2 is the same exacting pipeline every research peptide runs — but the chemistry plays out differently for this molecule. Here is how GHRP-2, specifically, is brought into being.
On paper, GHRP-2 is C45H55N9O6 — about 817.99 daltons of precisely arranged atoms. Before a single bond is made, the target sequence, salt form, and purity threshold are written down as the contract the finished material must meet.
GHRP-2's chain is short but unusual — it carries D-amino acids and non-natural residues that help it resist enzymatic breakdown, but demand specialized, costlier building blocks and careful coupling on the synthesizer. Its C-terminus is amidated rather than left as a free acid — a defined modification the synthesis has to deliver, not an afterthought.
The crude mixture — GHRP-2 plus its deletions and side products — is then separated on preparative HPLC, and where the cut is taken decides the difference between a genuinely pure peptide and a barely-passable one.
A real batch of GHRP-2 proves itself: identity confirmed by mass spectrometry against its ~817.99 Da, purity read directly off an analytical HPLC trace, water and counterion content measured. That batch-specific certificate of analysis is the only honest way to know what is actually in a vial of GHRP-2 — and a short, cold, accountable chain of custody is how that purity survives the trip to your bench.
A hexapeptide amide with two D-amino acids and an unnatural D-2-naphthylalanine at position 2. The chain is short and assembles cleanly by solid-phase synthesis; the quality-defining steps are sourcing and coupling the specialty D-2-Nal building block, controlling racemization at the D-residues, and achieving clean C-terminal amidation.
Don't judge a vial by its cake. A fluffy, good-looking lyophilized powder reflects bulking agents and freeze-drying parameters — not purity. Insist on a batch-specific certificate of analysis.
GHRP-2 (pralmorelin) is a synthetic hexapeptide that stimulates the pituitary to release growth hormone by activating the ghrelin receptor. In Japan it is an approved diagnostic for GH deficiency.
GHRP-2 is the more potent, more refined successor: it releases more GH per dose and causes much less of the sharp hunger GHRP-6 is known for.
Both are GHRPs, but ipamorelin is prized for releasing GH with minimal cortisol or prolactin; GHRP-2 is more potent yet less selective.
No. It is approved in Japan as a diagnostic (pralmorelin) but is not FDA-approved; in the US it is a research compound. This page is a research and educational reference.
Recombinant 191-amino-acid human growth hormone — a folded protein biologic identical in sequence to pituitary GH, not a synthetic research peptide.
ViewThe downstream effector of growth hormone — a 70-amino-acid recombinant protein, structurally a cousin of proinsulin, that carries out most of GH’s growth signal.
ViewA long-acting modified IGF-1 analog with reduced IGFBP binding and prolonged systemic activity.
ViewDosing protocols, mechanism, comparisons, and the latest trials — citation-backed answers grounded in PubMed, PubChem, and ClinicalTrials.gov.