Sermorelin: the monograph

Sermorelin is a synthetic 29-amino-acid fragment of human growth hormone-releasing hormone (GHRH) that carries the full GH-releasing activity of the parent hormone¹. Injected subcutaneously, it prompts the pituitary to release the body's own growth hormone in a short pulse rather than supplying growth hormone from outside².

Two facts frame everything else on this page. First, sermorelin is not an FDA-approved product today: it is sold through compounding pharmacies, and compounded drugs are not FDA-reviewed for safety, effectiveness, or quality before marketing³. Second, sermorelin once was approved: FDA cleared Geref (sermorelin acetate) for diagnostic use on December 28, 1990 and for pediatric therapy on September 26, 1997, and after the maker discontinued both products in 2008 FDA formally determined they were not withdrawn from sale for reasons of safety or effectiveness⁴.

This monograph lays out what the human trials actually measured, where the animal and mechanistic work stops, and which popular claims have no outcome evidence behind them. Every numbered citation resolves to a primary source.

Native human GHRH circulates mainly as a 44-amino-acid peptide. Structure-activity work in the 1980s showed the first 29 residues are the shortest fragment with full biological activity, and that fragment, GRF(1-29) amide, became the drug substance sermorelin acetate¹. FDA chemistry records for Geref describe the product as lyophilized sermorelin acetate powder for injection⁵.

The first therapeutic use in humans was reported in 1985, when two GH-deficient children received GRF by portable pump every 3 hours for 6 months and accelerated their growth from 4.6 to 7.1 cm/yr and from 2.1 to 13.7 cm/yr respectively⁶. Serono later developed sermorelin as Geref in two forms: a 0.05 mg ampoule for diagnostic testing of pituitary GH secretion (NDA 19-863, approved December 28, 1990) and 0.5 mg and 1.0 mg vials for pediatric growth hormone deficiency (NDA 20-443, approved September 26, 1997)⁴.

Today the molecule is prescribed off the approved-drug system entirely, through compounding pharmacies, most often marketed to adults interested in GH-axis support. That population was never the subject of the approval, and the adult evidence base is far thinner than the marketing suggests; the sections below quantify it⁷.

Sermorelin has the most unusual regulatory story of any compound in this site family, and it is worth telling precisely, because both its promoters and its critics tend to get it wrong.

Approved. Geref (sermorelin acetate) injection 0.05 mg base/amp was approved December 28, 1990 under NDA 19-863, indicated, in FDA's words, "for evaluating the ability of the somatotroph of the pituitary gland to secrete growth hormone." Geref 0.5 mg and 1.0 mg base/vial followed on September 26, 1997 under NDA 20-443, indicated, again quoting FDA, "for the treatment of idiopathic growth hormone deficiency (GHD) in children with growth failure."⁴

Discontinued. In letters dated July 11, 2008 and December 2, 2008, EMD Serono told FDA it was discontinuing the diagnostic ampoule and the therapeutic vials, and FDA moved both to the Discontinued Drug Product List section of the Orange Book⁴. Drugs@FDA still lists both applications with marketing status Discontinued⁸⁹.

Not a safety withdrawal. On March 4, 2013, responding to the question every generic maker must ask, FDA published a formal determination that the Geref products "were not withdrawn from sale for reasons of safety or effectiveness," a finding that legally opens the door to generic (ANDA) versions⁴. No company has brought one to market: Drugs@FDA shows no active sermorelin application, so no FDA-approved sermorelin product exists today⁹.

What fills the gap. Compounding pharmacies. FDA is explicit about what that means: "Compounded drugs are not FDA-approved. This means that FDA does not verify the safety, effectiveness or quality of compounded drugs before they are marketed."³ Unlike CJC-1295, ipamorelin, and most research peptides, sermorelin does not appear on FDA's list of bulk substances flagged for significant compounding safety risks; its history as an approved drug substance is the reason it occupies a gray zone rather than a red one¹⁰.

So the honest one-sentence version is: a formerly approved drug, dropped for business reasons, never pulled for safety, and never brought back through any FDA pathway.

There is no current FDA-approved dose of sermorelin for anyone, because there is no current FDA-approved product⁹. The figures below are the historical label dose and the doses used in published trials; they are reported for education, not as recommendations.

Pediatric label era. The approved Geref regimen studied in the pivotal trial was 30 mcg/kg subcutaneously once daily at bedtime in prepubertal GH-deficient children¹¹. A review of the program notes the growth effect was maintained through 36 months of continued dosing in the data available, and that height-velocity gains were smaller than those seen with daily somatropin at the same weight-based dose¹.

Diagnostic use. The diagnostic test used a single 1 mcg/kg intravenous dose to provoke a measurable GH response¹.

Adult research doses. Published adult protocols used 0.5 mg or 1.0 mg SC twice daily for 14 days,² 2 mg SC nightly for 6 weeks,¹² and 10 mcg/kg of a stabilized GHRH(1-29) analog nightly for 16 weeks¹³. Notably, the once-nightly 2 mg regimen raised overnight GH but did not move IGF-I at all over 6 weeks, while twice-daily dosing did; frequency mattered more than size¹².

Compounded products are dispensed in pharmacy-specific vial sizes and concentrations that FDA has not reviewed³. If a licensed clinician has prescribed sermorelin, the dose on that prescription label, not this page, governs; our reconstitution calculator only converts a prescribed dose into injection volume.

Sermorelin binds the GHRH receptor, a G-protein-coupled receptor on pituitary somatotroph cells, and stimulates both synthesis and pulsatile secretion of growth hormone. The receptor requirement is not hypothetical: mice carrying a single disabling mutation in this receptor secrete little GH and grow to dwarf proportions¹⁴.

Because sermorelin works upstream of the pituitary, the downstream control loops stay connected: GH output remains episodic rather than flat, as shown by frequent overnight sampling in treated older men, where injections amplified natural GH peaks instead of producing a continuous elevation². Even continuous GHRH infusion preserved pulsatile GH release in older men¹⁵. The GHRH-somatostatin-GH-IGF-I feedback system that regulates all of this is reviewed in detail elsewhere¹⁶.

The signal is deliberately brief. Plasma dipeptidylpeptidase IV (DPP-IV) removes the first two residues of GHRH peptides, including GRF(1-29), in a single cleavage that leaves a metabolite with under one thousandth of the original activity,¹⁷¹⁸ and the measured disappearance half-time of GHRH(1-29) in men is 4.3 minutes¹⁹. A nightly injection therefore delivers a transient prompt: in treated adults, GH rises within about 10 minutes and the induced pulse runs its course in roughly 2 hours¹³.

This is the core mechanical difference from injected growth hormone, which enters the circulation as the end hormone itself and does not depend on, or preserve, the pituitary's own release pattern; comparisons are drawn out in the dedicated section below²⁰.

The adult literature is real but small, and it measures hormones far more often than outcomes. The complete study table with species labels appears below this monograph; the highlights:

Hormone levels. In healthy men in their sixties and seventies, GHRH(1-29) 1.0 mg twice daily for 14 days raised 24-hour GH and IGF-I to ranges seen in untreated young men². A 16-week nightly regimen of a GHRH(1-29) analog raised nocturnal GH in both sexes, and raised IGF-I within 2 weeks, but IGF-I then drifted back toward baseline by week 16 despite continued injections¹³. A single nightly 2 mg dose for 6 weeks raised overnight GH yet changed neither IGF-I nor body composition¹².

Function and body composition. Across these trials the functional signals were modest and inconsistent: 2 of 6 strength measures improved in one uncontrolled 6-week study,¹² skin thickness increased in both sexes and lean mass in men only over 16 weeks,¹³ and no trial demonstrated fat-loss, fitness, or appearance outcomes that a buyer could bank on.

Sleep. GHRH participates in sleep regulation: bolus IV GHRH given late in the night produced a near 10-fold rise in slow-wave sleep in young men,²¹ and animal work shows GRF promotes non-REM sleep²². But timing dominates the effect, morning administration did nothing for slow-wave sleep,²³ and in the one long adult trial that asked, self-reported sleep quality did not improve over 16 weeks of nightly use¹³.

Reviews. Modern reviews of GH secretagogues in adults, sermorelin included, reach the same verdict we do: mechanistically coherent, clinically under-evidenced, with efficacy data that "largely remain lacking."⁷ A 2026 review of GH-axis peptides sold online classes the sector's recomposition and performance claims as unproven and flags the added uncertainty of unregulated supply chains²⁴.

The strongest sermorelin data were generated in the population it was approved for: prepubertal children with idiopathic growth hormone deficiency. In the multicenter registration-era trial, 110 previously untreated children received 30 mcg/kg SC at bedtime for up to a year; mean height velocity rose from 4.1 cm/yr to 8.0 cm/yr at 6 months and 7.2 cm/yr at 12 months, 74% were judged good responders at 6 months, and bone age advanced in step with height age rather than ahead of it¹¹.

The candid footnotes: catch-up growth occurred in the majority but not all children; the effect was documented out to 36 months without final-adult-height data; and the height-velocity gains were smaller than those achieved with once-daily somatropin at the same weight-based dose, a comparison never run head-to-head at the recommended regimens¹.

The diagnostic product had its own evidence track: a 1 mcg/kg IV dose provokes GH release rapidly and relatively specifically, with fewer false positives than conventional stimulation tests, though a normal response cannot exclude hypothalamic GH deficiency¹. In adults, combining GHRH with arginine became a standard provocative test, with a validated cut-off of 16.5 mcg/L versus 5 mcg/L for insulin-induced hypoglycemia²⁵.

None of this transfers automatically to the healthy adults who buy compounded sermorelin today; the pediatric data establish that the mechanism can produce a clinically meaningful outcome when the axis is genuinely deficient and the endpoint is growth.

No current FDA label exists for sermorelin, so there is no authoritative contraindication list for the compounded products sold today⁹. What follows is the closest honest substitute, drawn from the labeled GHRH analog still on the market and from the pharmacology.

Who should not consider sermorelin?

The FDA-approved GHRH analog tesamorelin (Egrifta SV) is contraindicated in active malignancy, in disruption of the hypothalamic-pituitary axis from surgery, irradiation, or head trauma, in pregnancy, and in known hypersensitivity; because sermorelin drives the same receptor and the same downstream axis, those exclusions are the rational starting point for any conversation about sermorelin²⁶. Growth factors are mitogens: reviews of GH-axis peptides flag biologically plausible, unproven mitogenic concerns as a standing reason for oncologic caution²⁴.

Anyone considering sermorelin without a prescriber has a simpler contraindication: FDA does not review compounded drugs for safety, effectiveness, or quality before marketing, so a licensed clinician and a licensed pharmacy are the only quality controls available at all³.

Formal interaction studies for compounded sermorelin do not exist, and the Geref-era label is out of distribution; reviews of this drug class note that interaction and safety data in modern self-administration contexts are simply not collected²⁴.

What is known to change the GH response?

Timing and physiology. The GH response to GHRH depends on when it is given: identical IV doses that raised slow-wave sleep and GH at night did not raise slow-wave sleep in the early morning, when cortisol activity is high²³.

Dosing frequency. Twice-daily dosing moved IGF-I where once-nightly dosing did not, an interaction of schedule rather than substance, but one with more measured impact than any drug pair on record for this molecule¹²².

Stacking. Online protocols commonly combine sermorelin with other GH-axis peptides; the 2026 peptide-landscape review emphasizes that the safety of such combinations is unstudied and that product composition in unregulated supply chains is itself uncertain²⁴. Tell every prescriber and pharmacist about all hormones and peptides in use; that is the entire reliable interaction guidance that exists.

What side effects were reported in trials?

Across the development program, single IV doses and repeated daily SC doses were described as well tolerated; the most commonly reported adverse events were transient facial flushing and pain at the injection site¹. In the 1-year pediatric trial no adverse changes in general biochemical profiles were reported¹¹. In adults, the 16-week nightly trial recorded transient hyperlipidemia that resolved by study end as its only adverse effect,¹³ and the 6-week nightly trial observed no significant adverse effects¹².

What has not been measured?

Long-term safety surveillance ended when the approved product left the market in 2008; no post-marketing safety system covers today's compounded use⁴. Class reviews of GH-axis peptides bought online report injection-site reactions, fluid retention syndromes, glucose disturbances, and hormonal imbalance across the category, and stress the uncertainty added by unverified product composition²⁴.

For calibration, the adverse-event profile of raising the axis pharmacologically is best documented for injected growth hormone itself: in pooled randomized trials in healthy older adults, GH caused significantly more soft-tissue edema, arthralgia, carpal tunnel syndrome, and gynecomastia, with a trend toward new diabetes and impaired fasting glucose²⁷. Sermorelin's gentler, pulse-preserving mechanism is often argued to lower those risks,²⁸ but no trial has demonstrated it.

Can sermorelin be used in pregnancy?

No published human data support sermorelin use in pregnancy or while breastfeeding, and no FDA-reviewed labeling exists to define the risk⁹. The one FDA-labeled drug in the same class, tesamorelin, is expressly contraindicated in pregnancy²⁶. Compounded sermorelin adds a second layer of unknowns because FDA does not verify the safety, effectiveness, or quality of compounded drugs before marketing³.

The education-grade bottom line: this is a category where the absence of evidence should be treated as a stop sign, not a blank check. Anyone pregnant, planning pregnancy, or breastfeeding should not use sermorelin outside a clinician-supervised setting, and should raise the topic with that clinician directly.

How should compounded sermorelin be stored?

Sermorelin acetate was supplied as a lyophilized (freeze-dried) powder for reconstitution, and FDA's 1991 supplement approval for Geref documents a shelf life of 24 months when stored refrigerated at 7 degrees C⁵. Peptide stability is temperature-sensitive; refrigeration of both the sealed vial and any reconstituted solution, protection from light, and prompt use after reconstitution are the standard handling pattern for this class.

Because every compounding pharmacy sets its own formulation, beyond-use date, and storage instructions, and FDA reviews none of them, the dispensing label from the pharmacy is the controlling document; when it conflicts with anything on this page, follow the label and ask the pharmacist³.

Every approved-era and trial regimen used small-volume subcutaneous injection: at bedtime in children,¹¹ and nightly or twice daily in the adult studies¹²². The diagnostic test used a single IV bolus in a supervised setting¹.

Why was dosing at bedtime?

The largest natural GH pulse of the day occurs shortly after sleep onset, in association with the first slow-wave sleep episode; in men roughly 70% of sleep GH pulses coincide with slow-wave sleep²⁹. Bedtime injection places the pharmacologic prompt where the physiologic one already lives, and the timing studies show that the same dose given in the early morning loses part of its effect profile²³.

Injection technique basics

The technique literature for subcutaneous therapies recommends short needles into the abdomen or thigh, and systematic rotation of injection sites so lipohypertrophy, the fat-pad thickening that distorts absorption, does not develop at overused sites³⁰. Our injection timing and rotation planner turns those recommendations into a printable schedule; it teaches technique concepts and never sets doses.

Every claim on this page carries a numbered citation that resolves to a primary source: peer-reviewed journals, FDA records, the Federal Register, and National Library of Medicine labeling. The full numbered list is below, and the same data ships as a machine-readable manifest at /evidence.json.

Direct answers to the questions readers actually bring to sermorelin, each with its sources; the first paragraph of every answer is the short version.

Sermorelin sits in a family of GH-axis molecules that are easy to conflate and importantly different. Tesamorelin is the only GHRH analog with a current FDA approval²⁶. CJC-1295 is a GHRH analog engineered for a days-long half-life, studied in healthy adults but never approved³¹. Ipamorelin works on a different receptor entirely, the ghrelin (GH secretagogue) receptor³². Both CJC-1295 and ipamorelin appear on FDA's compounding safety-risk list; sermorelin does not¹⁰.

Detailed cited comparisons: sermorelin vs HGH (somatropin), sermorelin vs CJC-1295 plus ipamorelin, and sermorelin vs tesamorelin.