# Sermorelin - Canonical: https://residue.info/c/sermorelin/ - Also called: GHRH(1-29)NH2, GRF 1-29, Geref - Evidence grade: A (Approved / regulatory-grade). Was FDA-approved (Geref, now discontinued) on pediatric data. Evidence for adult or anti-aging uses is limited and graded separately below. - Status: Approved product discontinued (Geref) - PubChem CID: 16132413 - Updated: 2026-10-19 · Reviewed by: Residue Editorial Team Sermorelin is a synthetic 29-amino-acid analog of growth-hormone-releasing hormone (GHRH) that stimulates the pituitary to release growth hormone [1]. It was approved by FDA as Geref, which is now listed as discontinued [2]. Clinical data come mainly from children with growth hormone deficiency, where it was less effective than growth hormone itself [3]. ## Key findings - Sermorelin is GHRH(1-29)-NH2, the shortest synthetic peptide with the full biological activity of GHRH; it stimulates GH secretion from the anterior pituitary [1]. (anchor: https://residue.info/c/sermorelin/#kf-pmid-18031173) - In a 1987 Lancet study of 18 GH-deficient children, height velocity rose in 12; 8 had a gain of more than 2 cm per year [4]. (anchor: https://residue.info/c/sermorelin/#kf-pmid-2879138) - In a randomized study of 60 children, mean height velocity at 6 months was 9.2 and 9.3 cm/year on two GHRH doses versus 14.6 cm/year on growth hormone [3]. (anchor: https://residue.info/c/sermorelin/#kf-pmid-8329830) - After an intravenous dose, sermorelin is rapidly eliminated, but GH stays elevated for about 3 hours; intranasal bioavailability was only 3–5% [5]. (anchor: https://residue.info/c/sermorelin/#kf-pmid-8329825) - Anti-GHRH antibodies developed in most treated children, without apparent effect on growth [3][4]. (anchor: https://residue.info/c/sermorelin/#kf-pmid-8329830-2) ## Effects by system - Growth (children with GHD) (grade A): Increased height velocity in some prepubertal children with idiopathic GH deficiency, but less than with somatropin [1][3]. (anchor: https://residue.info/c/sermorelin/#effect-growth-children-with-ghd) - Diagnostic testing (grade A): A single 1 µg/kg intravenous dose was described as a rapid, relatively specific test of pituitary GH reserve [1]. (anchor: https://residue.info/c/sermorelin/#effect-diagnostic-testing) - GH and IGF-1 (adults) (grade C): Raises GH acutely in healthy men [5]; data on long-term adult outcomes are limited [6]. (anchor: https://residue.info/c/sermorelin/#effect-gh-and-igf-1-adults) - Immunogenicity (grade B): GHRH antibodies in 39 of 40 children on continuous infusion; they had mostly disappeared 9 months after stopping [3]. (anchor: https://residue.info/c/sermorelin/#effect-immunogenicity) - Tolerability (grade B): Transient facial flushing and injection-site pain were the most common adverse events [1]. (anchor: https://residue.info/c/sermorelin/#effect-tolerability) ## How does Sermorelin work? Sermorelin reproduces the first 29 amino acids of human GHRH with an amidated C-terminus, GHRH(1-29)-NH2, the shortest synthetic peptide that retains the hormone's full biological activity [1]. Its residue sequence, from PubChem, is shown in Figure 1. Because it acts upstream of the pituitary, sermorelin's effect depends on the gland's capacity to respond. A review notes that a normal GH response to intravenous sermorelin cannot exclude GH deficiency caused by a hypothalamic problem [1]. ## How long does Sermorelin last in the body? In 30 healthy men, the lowest intravenous dose tested (0.25 µg/kg) produced significant GH release, with maximal peaks at 1–2 µg/kg. The peptide was rapidly eliminated, yet GH levels stayed elevated for about three hours. Nasal absorption was poor, with bioavailability of only 3–5%: roughly 50 µg/kg intranasally matched 1 µg/kg intravenously [5]. ## What did the clinical trials find? **Treatment of GH deficiency in children.** A 1987 Lancet report treated 18 prepubertal GH-deficient children with twice-daily subcutaneous GHRH(1-29)-NH2. Height velocity rose in 12, and 8 gained more than 2 cm/year over their pre-treatment rate (range 2.7–11.2 cm/year), sustained over 6–18 months. Four children who had previously received human GH grew more slowly on GHRH. The authors called it an alternative to GH for some children, with ideal dosing still to be established [4]. **Head-to-head with growth hormone.** A 1993 study randomized 60 children with GH deficiency of hypothalamic origin to GHRH(1-29)-NH2 at 30 or 60 µg/kg/day or to GH. After six months, height velocity was 9.2, 9.3 and 14.6 cm/year respectively — GH was significantly better. IGF-1 rose and then fell back to pre-treatment levels during GHRH infusion, and the authors concluded this approach was unlikely to be as effective as GH [3]. **The overall pediatric picture.** A 1999 review concluded that once-daily subcutaneous sermorelin given at bedtime was effective in treating some prepubertal children with idiopathic GH deficiency, with sustained increases in height velocity over 12 months and limited data to 36 months, but that its effect on final adult height had not been determined [1]. **Adults.** Interest in adult use — often framed as anti-aging — is far larger than the evidence. A 2006 review discussed sermorelin as an approach to adult-onset GH insufficiency [6]. The PubMed record contains many physiology studies that use GHRH(1-29) as a test agent [7], but these do not establish long-term benefit. ## What adverse events were reported in studies? Single intravenous doses and repeated subcutaneous doses were well tolerated in pediatric studies; transient facial flushing and injection-site pain were the most frequent events [1]. Antibodies against GHRH were common: they developed in 14 of 18 children in the 1987 study [4] and in 39 of 40 on continuous infusion in 1993, where they had nearly disappeared nine months after stopping and did not correlate with growth [3]. Drugs@FDA lists two Geref applications (original approvals in December 1990 and September 1997), both discontinued [2][8]. Sermorelin does not appear on FDA's Category 2 list of bulk substances with significant safety risks or among its withdrawn nominations [9]. ## What is still unknown? - **Final adult height** after long-term pediatric use was undetermined when the main review was written [1]. - **Adult outcomes** — body composition, function, safety over years — lack large randomized trials in the records we fetched. ## Frequently asked questions **Is sermorelin FDA-approved?** Sermorelin was approved as Geref under two FDA applications, from 1990 and 1997; both are now listed as discontinued in Drugs@FDA [2][8]. No currently marketed FDA-approved sermorelin product appears in the database. **How does sermorelin work?** It mimics growth-hormone-releasing hormone, binding pituitary GHRH receptors to stimulate the body's own growth hormone secretion [1]. Unlike growth hormone injections, it depends on a functioning pituitary. **What are the side effects of sermorelin?** In pediatric studies the most common were transient facial flushing and injection-site pain [1]; mild injection-site irritation was also reported [3]. Most treated children developed anti-GHRH antibodies [3]. **Is sermorelin as effective as growth hormone?** In children with GH deficiency, no: a randomized comparison found height velocity of about 9.2–9.3 cm/year on GHRH versus 14.6 cm/year on GH [3]. **Is there evidence for sermorelin in adults or for anti-aging?** Limited. Its acute effect on GH in healthy adults is documented [5], and its use in adult-onset GH insufficiency has been discussed [6], but we found no large randomized trial of long-term adult outcomes in the records we fetched. ## Sources [1] Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. Prakash A & Goa KL BioDrugs. 1999. https://pubmed.ncbi.nlm.nih.gov/18031173/ [2] Drugs@FDA: GEREF (NDA019863). EMD SERONO; original approval 1990-12-28; Discontinued. https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=019863 [3] A comparative study of growth hormone (GH) and GH-releasing hormone(1-29)-NH2 for stimulation of growth in children with GH deficiency. Chen RG et al. Acta Paediatr Suppl. 1993. https://pubmed.ncbi.nlm.nih.gov/8329830/ [4] Treatment of growth-hormone deficiency with growth-hormone-releasing hormone. Ross RJ et al. Lancet. 1987. https://pubmed.ncbi.nlm.nih.gov/2879138/ [5] Pharmacokinetics of growth hormone-releasing hormone(1-29)-NH2 and stimulation of growth hormone secretion in healthy subjects after intravenous or intranasal administration. Wilton P et al. Acta Paediatr Suppl. 1993. https://pubmed.ncbi.nlm.nih.gov/8329825/ [6] Sermorelin: a better approach to management of adult-onset growth hormone insufficiency?. Walker RF Clin Interv Aging. 2006. https://pubmed.ncbi.nlm.nih.gov/18046908/ [7] PubMed search: (sermorelin[tiab] OR "GHRH(1-29)"[tiab] OR "GRF(1-29)"[tiab]). 366 records at fetch. https://pubmed.ncbi.nlm.nih.gov/?term=(sermorelin%5Btiab%5D%20OR%20%22GHRH(1-29)%22%5Btiab%5D%20OR%20%22GRF(1-29)%22%5Btiab%5D) [8] Drugs@FDA: GEREF (NDA020443). EMD SERONO INC; original approval 1997-09-26; Discontinued. https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=020443 [9] Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. U.S. FDA, content current as of 04/22/2026. https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks --- From Residue. Research and education only; not medical advice. Quote with attribution and a link to the canonical page.