GHRP-2 (Pralmorelin)

GHRP-2 (pralmorelin) is a synthetic growth hormone-releasing peptide developed from the pioneering work of endocrinologist Cyril Bowers in the 1980s and 1990s. A small six-amino-acid peptide, GHRP-2 mimics the hormone ghrelin to trigger sharp pulses of growth hormone (GH), and it forms the basis of an approved diagnostic test for GH deficiency in Japan.

What is GHRP-2?

GHRP-2, also known as pralmorelin or KP-102, is a synthetic hexapeptide with the sequence D-Ala-D-2-Nal-Ala-Trp-D-Phe-Lys-NH2 (formula C45H55N9O6, about 818 g/mol). It is an agonist of the ghrelin / growth-hormone-secretagogue receptor (GHS-R1a) and belongs to the growth hormone-releasing peptide (GHRP) family alongside GHRP-6 and hexarelin. Importantly, GHRP-2 works through a different receptor than GH-releasing hormone analogs such as sermorelin or CJC-1295: those act on the GHRH receptor, while GHRP-2 acts on the ghrelin receptor.

How GHRP-2 is studied to work

GHRP-2 raises growth hormone by imitating ghrelin and pushing on several levers at once:

• Activates the ghrelin / GHS-R1a receptor on the pituitary and hypothalamus
• Stimulates a strong, pulsatile release of growth hormone
• Suppresses somatostatin, the body’s natural “brake” on GH
• Amplifies the action of the body’s own GH-releasing hormone
• Because it uses a separate pathway, it is often paired with a GHRH analog for a larger, synergistic GH pulse

Reported effects and benefits in the research literature

Effects reported for GHRP-2 in human and animal studies include:

• A robust rise in GH and IGF-1 — strong enough that GHRP-2 is used as a GH-stimulation diagnostic test
• Increased food intake: healthy men ate about 36% more after GHRP-2 versus placebo (Laferrère 2005)
• Studied for short stature and GH deficiency in children
• Investigated for effects on muscle, sleep quality and immune function

What this does NOT mean: these are measured research effects, not a recommendation or a dosing guide. Outside its diagnostic role, GHRP-2 remains investigational, and the appetite effect is a notable downside for some uses.

What the human evidence shows

GHRP-2 has its firmest footing as a diagnostic agent: it was approved in Japan in 2004 (as pralmorelin) for assessing growth hormone deficiency in adults and children, with phase II trials reporting high sensitivity for GH-stimulation testing. In healthy volunteers it reliably increases both GH secretion and food intake. Beyond diagnostics, its therapeutic use remains investigational — it is not FDA-approved as a treatment, and it is prohibited in sport by the World Anti-Doping Agency.

Handling, storage and reconstitution (research context)

GHRP-2 is supplied as a lyophilized (freeze-dried) powder and is reconstituted before use. General handling principles:

• Lyophilized powder: store frozen or refrigerated, protected from light
• Reconstitute with bacteriostatic water; once in solution, refrigerate and use within a few weeks
• Use the reconstitution calculator to convert vial strength and water volume into a concentration (mg/mL)
• See why units are not a dose before reading syringe markings

Cautions and considerations

• GHRP-2 is approved only as a diagnostic agent (Japan); other uses are investigational
• It reliably increases appetite, which may be undesirable depending on context
• Like other GH-raising compounds, it can affect fluid balance and blood sugar
• Confirm identity and purity with a Certificate of Analysis (COA)
• This page is informational only and is not medical advice

Frequently asked questions

What is the difference between GHRP-2 and GHRP-6?

Both are ghrelin-mimetic GHRPs. GHRP-2 is generally regarded as the more potent GH releaser for its size, while GHRP-6 tends to produce a stronger hunger response.

Does GHRP-2 increase appetite?

Yes. Because it acts on the ghrelin receptor, increased food intake is a well-documented and expected effect.

Is GHRP-2 approved or legal?

It is approved as a diagnostic agent in Japan but is not an approved therapy elsewhere, and it is banned in competitive sport by WADA.

Why is GHRP-2 combined with a GHRH analog?

Because the two act on different receptors, combining a GHRP with a GHRH analog produces a larger GH pulse than either alone — a synergy described in classic endocrine studies.

Related compounds and further reading

• Ipamorelin — a more selective GHRP with little appetite effect
• CJC-1295 (with DAC) — a GHRH analog commonly paired with GHRPs
• How to reconstitute peptides
• Sterile technique
• Peptide Library · Guides
• IU vs mL: why units are not a dose

For informational use only. Not medical advice; consult a qualified healthcare professional. 21+.