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.
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.
Where to get it
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