GH Secretagogues Hormonal Modulators Clinical use

Sermorelin

Also known as: GRF 1-29, Sermorelina, Geref

Sermorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) consisting of the first 29 amino acids of human GHRH, which make up the biologically active fragment. It stimulates the pituitary to produce and release its own GH in a physiological, pulsatile manner. It was FDA-approved (brand Geref) for the diagnosis and treatment of GH deficiency before being commercially discontinued.

Mechanism of action

Sermorelin acts on the GHRH receptor (GHRH-R) of pituitary somatotrophs.

GHRH-R agonism: activates adenylate cyclase and raises cAMP, inducing GH synthesis and release.
Physiological pattern: it preserves negative feedback by somatostatin, so GH release remains pulsatile and self-limiting.
IGF-1 increase: the released GH stimulates hepatic IGF-1 production.

Uses & indications

GH deficiency diagnosis (stimulation test).
Treatment of GH deficiency in children (historical approved use).
Anti-aging and hormone-optimization therapies (off-label).

Effects

Intended effects: physiological rise in GH/IGF-1, improved body composition, recovery and sleep.

Adverse effects: injection-site pain or redness, facial flushing, headache, dizziness and, rarely, taste alterations.

Considerations & contraindications

Requires a functional pituitary (it does not work if the deficiency is fully pituitary in origin).
Contraindicated in active cancer.
Monitor blood glucose in diabetics.

Regulatory approval

Historically FDA-approved as Geref for GH deficiency; commercially discontinued. Today mostly used in compounded formulations and off-label medicine.

Dosage

In historical/off-label practice 100–300 mcg at bedtime, subcutaneously, have been used. This is not a clinical recommendation.

Storage

Lyophilized: 2–8 °C. Reconstituted: refrigerate (2–8 °C) and use within 2–3 weeks; protect from light.

Technical data

Regulatory status Clinical use

Molecular weight 3357.9 Da

Half-life ~10–20 minutos

Administration routes Subcutánea