Quick summary
GHRH (Growth Hormone-Releasing Hormone) is the endogenous 44-amino acid hypothalamic peptide that drives pulsatile GH secretion. It serves as the structural template for FDA-validated analogs including sermorelin, CJC-1295, tesamorelin, and MOD-GRF 1-29.
Overview
GHRH is the endogenous 44-amino acid hypothalamic peptide that drives pulsatile growth hormone secretion from the anterior pituitary. It serves as the structural template for synthetic analogs sermorelin, CJC-1295, tesamorelin, and MOD-GRF 1-29. Research interest centers on its role in somatotropic axis regulation, aging, and body composition.
Mechanism of action
GHRH binds to the GHRH receptor (GHRHR) on somatotrope cells of the anterior pituitary, activating primarily the cAMP-dependent PKA pathway and secondarily the phospholipase C (IP3/DAG) pathway. Downstream signaling increases GH gene transcription and triggers exocytosis of GH-containing secretory granules. GHRH action is pulsatile and counterbalanced by somatostatin. The active region resides in the N-terminal 29 amino acids; the C-terminal 15 residues confer stability and receptor selectivity.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| GH stimulation testing | intravenous | 1–1 mcg/kg | single bolus | Administered as a single IV bolus for GH stimulation testing protocols |
| research / GH release | subcutaneous | 100–200 mcg | once daily | Synthetic analogs (sermorelin, MOD-GRF 1-29) are preferred over native GHRH for subcutaneous use due to stability |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Preclinical and clinical studies establish GHRH as the master regulator of GH pulsatility. Exogenous GHRH reliably increases IGF-1 and lean mass in GH-deficient states. Tesamorelin (a GHRH analog) is FDA-approved for HIV-associated lipodystrophy, validating the mechanism. Native GHRH(1-44) itself is primarily a research tool; pharmaceutical development has focused on longer-acting analogs. No completed trials of native GHRH as a standalone therapeutic as of 2026.[1][2][3][4]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with GHRH for synergistic effects.
Legal status
Native GHRH(1-44) is used as a research peptide. Synthetic analogs (sermorelin, tesamorelin) have received FDA approval for specific indications. Unmodified GHRH is not FDA-approved for clinical use.
Sourcing & access
Research compound
GHRH is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).
Frequently asked questions
GHRH (Growth Hormone-Releasing Hormone, also called Somatocrinin) is the 44-amino acid hypothalamic peptide responsible for stimulating pulsatile growth hormone secretion from the anterior pituitary. It is the natural template for all synthetic GHRH analogs used in research and medicine.
GHRH binds to the GHRH receptor on pituitary somatotrope cells, activating the cAMP/PKA pathway to increase GH gene transcription and trigger GH secretory granule release. Its action is pulsatile and counterbalanced by somatostatin. The active region resides in the first 29 amino acids.
Side effects include flushing, headache, transient hypotension, and injection site reactions. Native GHRH has a very short half-life of about 7 minutes, which limits its clinical utility. Synthetic analogs with longer half-lives are preferred for therapeutic use.
Tesamorelin, a GHRH analog, is FDA-approved for HIV-associated lipodystrophy, validating the GHRH mechanism. Sermorelin was previously approved for GH deficiency testing. MOD-GRF 1-29 and CJC-1295 are research analogs with improved stability over native GHRH.
Native GHRH(1-44) has an extremely short plasma half-life of approximately 7 minutes due to rapid enzymatic degradation. Pharmaceutical development has focused on longer-acting analogs that retain the mechanism but resist breakdown.
Research references
- Growth hormone-releasing hormone: structure, function, and therapeutic applicationsPubMed
- GHRH analogs and their effects on GH secretion and IGF-1 in adultsPubMed
- Tesamorelin (GHRH analog) reduces visceral adiposity in HIV-infected patientsPubMed
- GHRH-receptor signaling in somatotroph cells and GH axis regulationPubMed