Growth & GH-Axis

GHRP-2

Growth-hormone secretagogue (GHRP) / ghrelin receptor agonist

A synthetic GH-releasing peptide studied alongside GHRH analogs.

Also referenced as: Pralmorelin, Growth Hormone Releasing Peptide-2, KP-102, GPA-748

6 aat½ Short, on the order of tens of minutes (reported approximately 30-60 minutes)

Overview

GHRP-2 (pralmorelin) is a synthetic hexapeptide growth-hormone secretagogue. It has been used in Japan as a diagnostic agent for assessing growth-hormone secretory capacity.

At a glance

ClassGrowth-hormone secretagogue (GHRP) / ghrelin receptor agonist

CategoryGrowth & GH-Axis

SequenceD-Ala-D-2-Nal-Ala-Trp-D-Phe-Lys-NH2

Chain length6 amino acids

Molecular weight817.0 g/mol

Half-lifeShort, on the order of tens of minutes (reported approximately 30-60 minutes)

Typical formLyophilized powder

AliasesPralmorelin, Growth Hormone Releasing Peptide-2, KP-102, GPA-748

Use designationResearch / in-vitro only

Regulatory statusGHRP-2 (pralmorelin) is approved in Japan as a diagnostic agent for GH secretion testing but is not FDA-approved in the United States; outside that diagnostic use it is research-only.

What GHRP-2 does

GHRP-2 (pralmorelin) is a synthetic growth hormone-releasing peptide and a strong agonist of the ghrelin receptor (GHS-R1a). It stimulates GH secretion by the classic ghrelin-mimetic route — amplifying the amplitude of GH pulses from the pituitary and suppressing somatostatin — and does so reliably enough that it has been used clinically in Japan as a diagnostic agent to test pituitary GH reserve. That diagnostic use gives it a firmer human footing than most peptides here. As a secretagogue it acts on a pathway complementary to GHRH, so it is often studied in combination with a GHRH analog, where the two produce a markedly larger GH response than either alone.

Compared with ipamorelin, GHRP-2 is a more powerful but less selective GH releaser. In studies it produces meaningful GH and downstream IGF-1 increases, but it also modestly stimulates cortisol, ACTH, and prolactin, and it activates appetite through ghrelin-receptor signaling — though less intensely than GHRP-6. This off-target hormonal profile is the trade-off for its potency and is the key point distinguishing it within the GHRP family.

Human data come mainly from GH-stimulation/diagnostic studies and early pharmacology; beyond its diagnostic role it is a research compound, and there are no large trials establishing body-composition or performance benefits.

Effects reported in research

Stimulated a robust GH pulse via GHS-R1a agonism (established in human GH-stimulation studies).
Used clinically (in Japan) as a diagnostic test of pituitary GH secretory reserve.
Raised downstream IGF-1 following GH release.
Modestly increased cortisol, ACTH, and prolactin (less selective than ipamorelin).
Stimulated appetite via ghrelin-receptor signaling, though less strongly than GHRP-6 (human/animal).
Produced a much larger combined GH response when co-administered with a GHRH analog (synergy studies).
Suppressed somatostatin as part of its secretagogue mechanism.
No large trials for body composition/performance; research-use outside its diagnostic role.

Effects listed reflect findings reported in the research literature — many in animal or in-vitro models. Listing an effect is not a claim of efficacy or a therapeutic indication in humans.

Mechanism of action

GHRP-2 is an agonist of the growth-hormone secretagogue receptor (GHS-R1a, ghrelin receptor), stimulating pulsatile GH release from the pituitary. It is a potent GH secretagogue and also stimulates appetite via ghrelin-receptor signaling. It can modestly increase ACTH, cortisol, and prolactin, though generally less than GHRP-6 for appetite effects.

Mechanistic description reflects published research-literature understanding. Much peptide research is preclinical (in-vitro or animal-model); mechanism in humans may differ and is not established for many compounds.

What it's studied for

Research contexts in which GHRP-2 appears in the literature. Listing a research area is not a claim of efficacy or a therapeutic indication.

Key characteristics

Potent GHS-R1a (ghrelin receptor) agonist and strong GH releaser
Approved in Japan as a diagnostic agent (pralmorelin) for GH secretion testing
Stimulates appetite via ghrelin-receptor signaling
Can modestly raise cortisol and prolactin, less selective than ipamorelin
Hexapeptide of the GHRP family

Reported research dosing reference only

Educational reference, not dosing guidance. The figures below summarize amounts reported in published research and research-community protocols, provided for educational and research context only. They are not medical advice, not a recommendation, and not instructions for human use. GHRP-2 is a research compound.

GHRP-2 is referenced in research protocols in the ~100-200 mcg per-dose range, with diminishing returns above roughly 300 mcg per dose. These are reference figures for research context only, not dosing guidance for humans.

Common research-protocol reference: 100-200 mcg per subcutaneous dose
Reported saturation/diminishing returns above ~300 mcg per dose
Diagnostic GH-stimulation testing referenced ~1 mcg/kg boluses

Reported frequencyReported 2-3 times daily in research protocols, often fasted

ReconstitutionLyophilized; typically reconstituted with bacteriostatic water for research use

Elevates cortisol/prolactin more than ipamorelin or GHRP-6; ~30 min half-life. Reference figures only, not human dosing guidance.

How it compares

GHRP-2 is a potent GH releaser with an approved diagnostic use in Japan (pralmorelin), and it stimulates appetite, distinguishing it from the more selective ipamorelin.

Commonly studied alongside

Compounds frequently researched together with GHRP-2 in the literature. Cross-referenced for research context — not a usage or combination recommendation.

CJC-1295 (with DAC)Ghrelin-receptor GHRP + GHRH analog is a synergistic GH-release research pairing.SermorelinCo-studied to combine ghrelin-receptor and GHRH-receptor stimulation for amplified GH pulses.CJC-1295 (no DAC)Short-acting GHRH analog paired with GHRP-2 to model pulsatile combined GH release.

Compare and calculate

Side-by-side pages for the pairings the literature already documents for GHRP-2, plus the unit-conversion reference for a reconstituted vial. Factual comparisons of documented characteristics — not a recommendation to combine or use any compound.

Handling & Stability

Lyophilized peptides are stored cold, protected from light, and reconstituted only at the time of intended in-vitro work.

Avoid repeated freeze-thaw cycles
Verify supplier lot and Certificate of Analysis
Follow institutional lab-safety protocols

Analytical & COA Concepts

Reputable research suppliers publish a third-party Certificate of Analysis per batch. Key analytical concepts referenced in COAs include:

Category Context

GHRP-2 sits in the Growth & GH-Axis area of the PeptiDex library.

Research Supplier Listing

Where researchers source GHRP-2

For researchers studying GHRP-2, third-party suppliers such as Practically Natty Peptides offer research-grade material, third-party tests every batch and provides Certificates of Analysis on request, and ship from the US.

Explore Research Suppliers →

PeptiDex does not maintain a direct supplier listing for this compound. The link above goes to a third-party research-supplier directory.

Frequently asked questions

What is GHRP-2 (pralmorelin)?

GHRP-2, also called pralmorelin, is a synthetic hexapeptide growth hormone-releasing peptide that activates the ghrelin receptor (GHS-R1a) to stimulate pulsatile GH secretion from the anterior pituitary. It is one of the most clinically studied GHRPs and was developed as a diagnostic agent for GH deficiency.

How does GHRP-2 differ from ipamorelin?

Both activate the ghrelin receptor, but GHRP-2 is a stronger GH stimulus that also produces more transient elevation of cortisol and prolactin, whereas ipamorelin is more selective with minimal effect on those hormones. Research design often chooses between them based on whether off-target hormone effects are acceptable.

Does GHRP-2 increase appetite?

Yes, though generally less than GHRP-6. As a ghrelin-receptor agonist, GHRP-2 is reported to modestly increase appetite in the research literature, consistent with the hunger-signaling role of ghrelin.

Why is GHRP-2 studied with a GHRH analog?

GHRP-2 stimulates the ghrelin receptor while GHRH analogs (CJC-1295, sermorelin) stimulate the GHRH receptor. Combining the two produces a synergistic GH pulse larger than either pathway alone, a widely referenced approach in GH-secretagogue research.

Is GHRP-2 an approved drug?

GHRP-2 (pralmorelin) has been used clinically in some countries as a diagnostic agent for GH deficiency, but it is not FDA-approved in the United States and is otherwise handled as a research chemical.

Answers are educational summaries of research-literature context and do not constitute medical advice. See the Research Library, COA guide, and Storage & Handling guide for more.

References

Primary literature indexed in PubMed for GHRP-2. Listing a study records that it exists and is indexed — it is not a claim of efficacy, a therapeutic indication, or an endorsement of its conclusions. Much of this literature is preclinical (in-vitro or animal-model).

Growth hormone releasing peptide-2 (GHRP-2), like ghrelin, increases food intake in healthy men J Clin Endocrinol Metab, 2005. PubMed 15699539
Pharmacological characteristics of KP-102 (GHRP-2), a potent growth hormone-releasing peptide Arzneimittelforschung, 2004. PubMed 15646370

Each reference was checked against its PubMed record on 2026-07-28: the PMID resolves and the title, journal and year match. Where no indexed literature exists for a compound, PeptiDex says so rather than substituting a citation about a different molecule. See the editorial policy.