Sermorelin is a once-FDA-approved GHRH(1-29) growth hormone secretagogue, read here as verifiable status, not marketing.

The short version

Sermorelin is a lab-made copy of the active front piece of a natural brain hormone that tells the pituitary gland to release the body's own growth hormone. It is not growth hormone itself — it is the upstream signal. In the 1990s a prescription form was approved in the United States to help short, growth-hormone-deficient children grow; that branded product was pulled from the market in 2008 for business reasons, not because it was unsafe, and the molecule is now made by compounding pharmacies. This page lays out what sermorelin is, what studies measured, and where the regulatory record actually stands — each fact tied to its source.

What the sermorelin record actually establishes

Sermorelin (sermorelin acetate, GHRH(1-29)NH2) is a synthetic 29-amino-acid peptide — the amino-terminal 1-29 fragment of human growth hormone-releasing hormone (GHRH, the 44-amino-acid hypothalamic hormone that signals the pituitary to make growth hormone). It is the shortest fragment that keeps full activity at the GHRH receptor. Its molecular weight is 3357.9 Da and its CAS number is 86168-78-7.

The regulatory facts are verifiable and frequently misstated. Sermorelin was FDA-approved as a prescription GHRH analog (NDA 020443) for evaluating and treating idiopathic growth hormone deficiency and short stature in children. The branded US product was withdrawn from the market in 2008 for commercial reasons — not over any safety or efficacy problem. It remains available through compounding pharmacies and is treated as a long-standing Category 1 bulk drug substance under FDA's interim Section 503A policy (final guidance January 2025). "Formerly FDA-approved, now compounded" is the accurate frame; "never approved" and "currently FDA-approved" are both wrong.

The efficacy record is strongest where the approval was. 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 excessive IGF-1 generation ^[1]. In healthy older men, 0.5 mg and 1 mg subcutaneously twice daily for 14 days produced dose-related increases in 24-hour growth hormone (GH) and IGF-1 (insulin-like growth factor 1, the liver hormone that carries out most of GH's downstream effects); at the high dose, their GH/IGF-1 parameters no longer differed from those of young men ^[2]. What the research shows collects these findings in full.

What is sermorelin?

Sermorelin (sermorelin acetate, GHRH(1-29)NH2 / GRF(1-29)) is a synthetic 29-amino-acid peptide matching the N-terminal 1-29 fragment of human growth hormone-releasing hormone — the shortest fragment that retains full activity at the GHRH receptor. It is a pituitary growth hormone secretagogue (a substance that prompts a gland to secrete): it does not supply growth hormone, it prompts the body to release its own.

Because it acts upstream on the pituitary rather than delivering external GH, the body's own brakes stay in place. Somatostatin (the hypothalamic hormone that opposes GHRH and shuts GH release off) and IGF-1 feedback continue to regulate output, so the natural pulsatile rhythm of GH secretion is preserved. One editorial author argued on exactly this basis that sermorelin may be a more physiologic approach to adult-onset growth hormone insufficiency than recombinant growth hormone ^[4].

Sermorelin acetate: chemistry and form

Sermorelin is supplied as sermorelin acetate, the lyophilized (freeze-dried) acetate salt of the GHRH(1-29)NH2 peptide. The amino-terminal amide group on residue 29 is part of what gives the fragment full receptor activity. Molecular weight is 3357.9 Da; the molecular formula of the free peptide is C149H246N44O42S; CAS is 86168-78-7 (114466-38-5 for the acetate). PubChem lists CID 16132413.

The acetate is shipped as a dry powder because peptides in aqueous solution degrade; it is reconstituted with sterile diluent and then typically refrigerated. Compounded preparations are prepared under USP <797> sterile-compounding standards. The molecule itself is not a controlled substance under the Controlled Substances Act.

What does sermorelin do to the body?

Sermorelin binds GHRH receptors (a class B G-protein-coupled receptor) on anterior-pituitary somatotrophs — the specific pituitary cells that make growth hormone. That binding activates the Gs / adenylate cyclase / cAMP / protein kinase A pathway (a standard intracellular signaling chain that turns a receptor signal into a cellular response), driving synthesis and pulsatile release of GH. Circulating GH then prompts the liver to produce IGF-1.

In healthy men, intravenous GHRH(1-29)NH2 triggered significant GH release at doses as low as 0.25 mcg/kg, with maximal release around 1-2 mcg/kg ^[3]. The honest counterweight is that long-term efficacy and safety data for adult "anti-aging" use remain limited, and an Annals of Internal Medicine editorial judged growth-hormone-secretagogue use for aging "not yet ready for prime time" ^[5] — the marketing has run ahead of the evidence.

Reading the rest of this site

This site is organized as a status console: each fact carries its source and its operational state. The regulatory spine — the FDA approval and 2008 withdrawal — lives on the pediatric page, because that is where the approval actually was and where the multicenter height-velocity trial sits. The durability story, sermorelin vs tesamorelin, explains why a peptide that clears in ten minutes spawned a family of longer-acting analogs. The doses used in the research page reports study protocols only, never a human regimen. The full GH/IGF-1 record, the cognition signal, and the reported side effects are collected on what the research shows, and every quantitative claim resolves to the full reference list with PMIDs and DOIs.

Two guardrails hold across all of it. First, sermorelin is a growth hormone secretagogue prohibited in sport by WADA (S2). Second, nothing here is a dosing recommendation — the site describes what studies measured, in which species, at which dose, by which route.