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GHRP-2

unknown risk

Also: Pralmorelin · KP-102 · GH-Releasing Peptide-2

Preliminary Research Only

GHRP-2 is a synthetic hexapeptide growth hormone secretagogue with potent GH-releasing activity. It is one of the most studied GHRPs, with established human pharmacokinetic and pharmacodynamic data, though no FDA approval for therapeutic use.

Molecular Weight
817.0 g/mol
Formula
C45H55N9O6
Common Dosing
100-300 mcg 2-3x daily subcutaneous (from literature)
Category
research
Last Reviewed
2025-01-15

Reported Benefits

GH Release

Preliminary 20 studies

Robust GH secretion demonstrated across multiple human studies and age groups.

Body Composition

Insufficient 4 studies

Extrapolated from GH physiology; no direct human RCT data for body composition.

Appetite Stimulation

Preliminary 8 studies

Significant appetite increase via ghrelin receptor mechanism — notable effect vs ipamorelin.

Mechanism of Action

GHRP-2 binds the ghrelin receptor (GHSR) on pituitary somatotrophs and hypothalamic neurons, triggering GH release. It also stimulates ACTH/cortisol release more potently than GHRP-6 or ipamorelin. Combined with GHRH analogs, it produces synergistic GH secretion through complementary receptor pathways.

Key Clinical Studies

Bowers CY et al. (1991)

pharmacodynamic · Healthy adults

PubMed →

Potent dose-dependent GH release; first characterization of GHRP class

Hartman ML et al. (1992)

crossover RCT · 24 adults

GHRP-2 + GHRH synergistically increases GH release

Overview

GHRP-2 is the most studied and characterized GHRP class peptide. Originally developed as a pharmacological tool for studying GH secretion, it established the proof-of-concept that small synthetic peptides could robustly stimulate GH release — a finding that eventually led to the development of ipamorelin and oral secretagogues like MK-677.

The GHRP Class Pioneer

The Bowers laboratory at Tulane University characterized GHRP-2 in the early 1990s, establishing the synthetic peptide GH secretagogue concept. This work won Cyril Bowers significant recognition and directly influenced the pharmaceutical development of the GH secretagogue class.

Cortisol Concern

GHRP-2’s significant cortisol stimulation (via ACTH) is a clinical consideration. Cortisol is catabolic, and its elevation partially counteracts the anabolic/body composition benefits of GH secretion. This is why ipamorelin (much lower cortisol stimulation) has largely supplanted GHRP-2 in clinical anti-aging protocols.

Appetite Effect

GHRP-2 potently stimulates appetite — a direct ghrelin-mimetic effect. This is a feature in cachectic patients (cancer, HIV wasting) but a problem for patients pursuing weight management. This characteristic further differentiates it from ipamorelin in clinical selection.

Regulatory Status

Research Only

Not FDA-approved; previously used as diagnostic agent in some countries

Safety Profile

Side Effects

  • Increased appetite
  • Cortisol elevation
  • Prolactin elevation
  • Water retention
  • Flushing

Contraindications

  • Active malignancy
  • Pregnancy
  • Diabetes (GH increases insulin resistance)

Drug Interactions

  • Insulin
  • Glucocorticoids
  • Somatostatin analogs

Primary Uses

GH secretagogueBody compositionAnti-agingAppetite stimulation

Weekly Briefing

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Disclaimer: This information is for educational and research purposes only. Not medical advice. Consult a qualified healthcare provider before using any compound.