Growth hormone axis
GHRP-2
One of the original growth-hormone secretagogue peptides — real pharmacology, no approved physique indication, and formal FDA compounding safety concerns.
Also known as: pralmorelin, growth hormone releasing peptide-2
Evidence passport
Last reviewed 2026-08-23
- Evidence level
- L2Preclinical
- Confidence
- Very low confidence
- Human efficacy
- 25/100
- Human safety
- 12/100
- Regulatory status
- Experimental / research
- Development
- Unclear
- Routes
- SC injection· unapprovedNasal· unapproved
- Evidence base
- Mostly preclinical
- Furthest stage
- Not established
- Source curation
- Sources fully curated
- Clinical maturity
- Historical human pharmacology studies; no approved therapeutic programme
Most of this evidence comes from animals and cells
Overview
Clinical maturity: Historical human pharmacology studies; no approved therapeutic programme
Routes & formulations
Marketed / research routes — never approved
FDA material describes injectable and nasal marketed products. These are unapproved routes for the marketed claims; their availability is not evidence of efficacy.
Route availability is not evidence of efficacy, and evidence from one route does not transfer to another. The Registry never provides dosing or sourcing information.
Peptide lifecycle
Discovery
Preclinical
Phase I
Phase II
Phase III
Approved
Historical clinical pharmacology research exists; no established current development programme in the curated record.
What it is
A synthetic hexapeptide that stimulates growth hormone release via the ghrelin receptor, part of the first wave of GH secretagogue research.
What people claim
- Raises growth hormone for muscle gain and fat loss
- Anti-ageing GH restoration
What the evidence actually says
GHRP-2 genuinely raises GH and IGF-1 — that was established in early human pharmacology studies. What was never established is the part people buy it for: no controlled trials demonstrate body-composition, performance or anti-ageing benefit. A hormone change is a surrogate, not an outcome.
Human evidence
- Early human pharmacology studies confirming GH release.
- Published serious adverse event case reports noted by the FDA; case reports signal possible harm but do not by themselves prove causation for every event.
- No controlled trials supporting physique, performance or anti-ageing claims.
Preclinical evidence
- Ghrelin-receptor pharmacology and animal GH-axis studies.
Animal and cell findings are Level 1–2 evidence.
Mechanism and pathways
- GHSR-1a agonism on pituitary somatotrophs and hypothalamic circuits drives GH pulses.
Safety and unknowns
- The FDA flags immunogenicity and impurity concerns and cites published serious adverse event case reports for compounded use.
- Chronic GH-axis stimulation has unresolved long-term safety questions.
Cancer relevance
Theoretical / mechanistic concern only
Regulatory status
Not an FDA-approved medicine. The FDA's compounding safety material flags GHRP-2 across injectable and nasal routes, citing immunogenicity and impurity concerns and published serious adverse event case reports.
Evidence grade
Animal, organoid or tissue studies. Mice are not tiny humans.
What would change our rating?
- Controlled trials with functional or body-composition endpoints.
- A modern systematic safety dataset.
References and sources
- Regulatory / labelFDA — Certain bulk drug substances for use in compounding that may present significant safety risks
Source hierarchy: regulatory documents and trial registries first, peer-reviewed work next, sponsor material flagged as non-independent. We never use supplier or clinic marketing as evidence, and where a verified source has not yet been curated we say so rather than inventing one.
Evidence change history
No recorded changes yet. Baseline position set on 2026-08-23.