Sermorelin is the GHRH(1-29) growth-hormone-releasing peptide, read here through its safety record and body-composition research.

The short version

Sermorelin is a small peptide — 29 amino acids — that copies the front end of GHRH (the brain's own "make growth hormone" signal). It is a secretagogue (something that tells a gland to release its hormone): it nudges the pituitary to put out the body's own growth hormone (GH) in natural bursts, which then raises IGF-1 (a growth signal the liver makes when GH rises). It was once an FDA-approved medicine for children who grew too slowly, was pulled from the US market in 2008 for business reasons — not safety — and is now made by compounding pharmacies. This site is a plain-English reading of what the studies actually found, with every number sourced.

Sermorelin: The GHRH(1-29) Peptide

Sermorelin is the amino-terminal 1-29 fragment of growth hormone-releasing hormone — the shortest piece of the 44-residue parent hormone that still keeps full activity at the GHRH receptor ^[3][14]. In the literature it carries several names: GHRH(1-29), GRF(1-29), GRF(1-29)NH2. As a sermorelin peptide, it is a synthetic chain of 3357.9 daltons, built to mimic a signal the body already uses every night.

Its mechanism is upstream, not replacement. Sermorelin binds the GHRH receptor on anterior-pituitary somatotrophs (the GH-producing cells), switching on the adenylate-cyclase / cAMP / protein-kinase-A pathway that drives synthesis and release of the body's own GH ^[14]. Because it acts on the gland rather than supplying outside GH, the natural brakes stay intact: somatostatin (the hormone that inhibits GH) and IGF-1 feedback keep the pulse pattern physiologic ^[4][14]. That distinction — stimulating an own-supply versus replacing it — is the whole reason the molecule was studied as a more physiologic approach to adult-onset GH insufficiency than recombinant GH ^[4]. Read the full account of how sermorelin works below, or jump to what the research says.

Sermorelin Acetate

The compounded and research form is sermorelin acetate — the amidated acetate salt of the GHRH(1-29) fragment (CAS 86168-78-7; the acetate salt, CAS 114466-38-5). Amidation of the C-terminus is part of what gives the short fragment its full receptor activity. It is supplied as a lyophilized (freeze-dried) powder because aqueous peptide solutions degrade; once reconstituted it is refrigerated, and compounded preparations are made under USP sterile-compounding standards. None of that is a dosing instruction — it is the handling context the literature describes.

What the Research Says About Sermorelin

The strongest evidence sits where the molecule was originally approved. In a multicenter trial of prepubertal growth-hormone-deficient children, once-daily subcutaneous GHRH(1-29) raised first-year height velocity from about 4.1 cm/year to roughly 7-8 cm/year, without driving IGF-1 above the normal range ^[1]. That is a controlled, on-label result.

In adults the signals are real but narrower. In healthy older men (mean age 68), twice-daily GHRH(1-29) at 0.5 mg and 1 mg for 14 days produced dose-related rises in 24-hour GH and IGF-1; after the high dose, their GH/IGF-1 parameters no longer differed from those of young men, with no change in fasting glucose ^[2]. Over 16 weeks, age-advanced men and women self-injecting an analog of the fragment nightly showed rising IGF-1 and IGFBP-3, with no change in blood pressure or body weight ^[9]. The honest counterweight: an Annals of Internal Medicine editorial judged the use of GH secretagogues to slow aging "not yet ready for prime time" ^[5]. Both statements are true at once, which is the point of reading the record rather than the marketing.

The topics branch from here: doses used in research, sermorelin half-life, sermorelin and body composition, and side effects reported in studies. The common questions about sermorelin collect the rest.

The status board: formerly approved, now compounded

Sermorelin's regulatory history is the single fact most often misstated, so it belongs on the front of the board. It was a genuine FDA-approved prescription drug for evaluating and treating growth-hormone deficiency and short stature in children ^[1]. It was withdrawn from the US market in 2008 for commercial reasons — not because of any safety or efficacy problem. "Formerly approved" is not "never approved," and it is not "banned."

What it is today: a compounded preparation. Sermorelin is treated as a long-standing Category 1 bulk drug substance under FDA's interim Section 503A framework (with final guidance issued in January 2025), the category against which the agency does not intend enforcement action. It is not a currently-marketed FDA-approved finished drug, and it is not a controlled substance under the Controlled Substances Act. In sport, GH secretagogues — including GHRH analogs like sermorelin — are prohibited by WADA. Those four lines are the honest status board: formerly approved, now compounded, not scheduled, prohibited in competition.

What sermorelin is not

Three boundaries keep the reading clean. First, the adult body-composition and anti-aging claims attached to sermorelin outrun the controlled evidence — the credible fat and IGF-1 numbers in this drug class largely belong to the related analog tesamorelin, not to sermorelin itself ^[6][11], and this site keeps that line drawn on its sermorelin and body composition page. Second, oral, sublingual, and troche "sermorelin" products are widely criticized as ineffective, consistent with the very low (~3-5%) absorption reported even for the intranasal route ^[3]. Third, the research-grade sermorelin this digest describes is supplied for laboratory work — not as a finished medicine to self-administer — which is why every figure here is reported as "studied at X in [population]" and never as a dose to take.

What does sermorelin do to the body?

It binds GHRH receptors on pituitary somatotrophs and stimulates the body's own pulsatile growth-hormone release, which raises liver-made IGF-1 ^[14]. Because it acts upstream — on the gland rather than supplying outside hormone — somatostatin and IGF-1 feedback stay intact, preserving the natural burst pattern of secretion rather than flattening it ^[4].