GHRP-2
Growth Hormone SecretagogueresearchAlso known as: Growth Hormone Releasing Peptide 2, Pralmorelin, KP-102, GHRP-II
A synthetic hexapeptide growth hormone secretagogue considered to offer the best balance of potency and side effect profile among the GHRP family.
Overview
GHRP-2 (Growth Hormone Releasing Peptide 2) is a synthetic hexapeptide that stimulates growth hormone secretion by activating the ghrelin receptor (GHS-R1a). It is widely regarded as the most balanced GHRP, offering strong GH release with moderate effects on cortisol, prolactin, and appetite — sitting between the aggressive GHRP-6 and the milder ipamorelin. GHRP-2 has been extensively studied in clinical trials and is approved in Japan under the name pralmorelin as a diagnostic agent for GH deficiency. It is popular in anti-aging, bodybuilding, and performance communities for its reliable GH-boosting effects and synergy with GHRH peptides.
Mechanism of Action
GHRP-2 activates the growth hormone secretagogue receptor (GHS-R1a) on pituitary somatotrophs, amplifying pulsatile GH release. It works synergistically with endogenous GHRH and also suppresses somatostatin's inhibitory effect on GH secretion. GHRP-2 stimulates the hypothalamic-pituitary axis through both direct pituitary action and hypothalamic GHRH neuron activation. It mildly stimulates ghrelin-like signaling, causing modest increases in appetite, cortisol, and prolactin.
Molecular Formula
C45H55N9O6
Molecular Weight
817.97 g/mol
Sequence
D-Ala-D-2-Nal-Ala-Trp-D-Phe-Lys-NH2
Dosage Protocols
Dose Range
100mcg – 300mcg
Frequency
2-3 times daily
Route
subcutaneous
Cycle Length
8-16 weeks
Administer on an empty stomach (no food 30 min before or after). Most effective pre-bed and post-workout. Synergistic when combined with a GHRH analog like CJC-1295.
Source: Clinical trials and community protocols
Side Effects
| Effect | Severity |
|---|---|
| Increased appetite | mild |
| Elevated cortisol | mild |
| Elevated prolactin | mild |
| Water retention | mild |
| Injection site irritation | mild |
| Drowsiness | mild |
Pros & Cons
Considered the best balance of GH potency and side effects among all GHRPs
Extensively studied in human clinical trials with well-established pharmacology
Approved pharmaceutical product in Japan (pralmorelin), confirming clinical-grade evidence
Strong synergy with GHRH analogs for amplified GH release
Less desensitization compared to hexarelin with proper cycling
Moderate appetite stimulation may be undesirable for those trying to lose fat
Still raises cortisol and prolactin, unlike the cleaner ipamorelin
Not FDA-approved in the US or Europe; limited to research chemical status in most countries
Requires fasted administration for optimal GH release
Research Studies
Legal Status
Approved in Japan as a GH-deficiency diagnostic (pralmorelin). Not FDA-approved in the US. Available as a research chemical. Banned by WADA.
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