Sermorelin is the GHRH(1-29) fragment, read here through its growth hormone and IGF-1 evidence.

The short version

Sermorelin is a short peptide — a chain of amino acids — that copies the front end of a brain hormone called GHRH (the 'make growth hormone' signal the hypothalamus sends to the pituitary). It does not supply growth hormone. It tells your own pituitary to release its own, in the natural pattern of bursts. In growth-hormone-deficient children it sped up growth ^[1]. In healthy older men it raised growth hormone and IGF-1 in a dose-related way ^[2]. The adult anti-aging marketing, though, runs ahead of the evidence — and this page says so plainly ^[5].

What sermorelin is, on the record

Sermorelin (sermorelin acetate) is the amidated synthetic 1-29 fragment of growth hormone-releasing hormone — the first twenty-nine amino acids of the body's own 44-residue GHRH, and the shortest fragment that retains full activity at the GHRH receptor. Its molecular weight is roughly 3,358 Da and its CAS number is 86168-78-7.

It is a secretagogue — something that tells a gland to release its own hormone. Sermorelin binds GHRH receptors on the anterior pituitary's somatotrophs (the growth-hormone-producing cells) and prompts them to release growth hormone (GH) in the body's natural pulsatile pattern — in discrete bursts rather than a flat infusion ^[4]. Because it acts upstream, the body's own brakes (the inhibitory hormone somatostatin and IGF-1 feedback) stay intact.

The regulatory history is precise and often told wrong. Sermorelin was an FDA-approved drug for evaluating and treating growth hormone deficiency in children; it was withdrawn from the US market in 2008 for commercial reasons, not for any safety or efficacy failure. It is now prepared by compounding pharmacies. This site treats it as a research-grade subject and a literature record — not a product, and nothing here is dosed, dispensed, or sold.

Sermorelin peptide: where it sits in the secretagogue family

As a research peptide, sermorelin sits in the GHRH-analog branch of the growth-hormone secretagogue family. It is the native human GHRH(1-29) sequence rather than a chemically stabilized analog, which has two consequences that recur across the literature.

First, it is cleared quickly: the native peptide's plasma half-life is on the order of ten to twelve minutes after intravenous dosing, even though a single dose keeps serum GH elevated for about three hours ^[3]. That brevity is exactly what motivated the longer-acting analogs — the sermorelin vs CJC-1295 comparison turns on it.

Second, because sermorelin works through the pituitary's own machinery, the GH it releases arrives in pulses with feedback intact — an argument one editorial made for the secretagogue route being more physiologic for adult GH insufficiency than supplying recombinant hormone directly ^[4]. The deeper read of the mechanism at the GHRH receptor lives in the research findings.

What the studies actually measured

In a multicenter trial of prepubertal growth-hormone-deficient children, once-daily subcutaneous GHRH(1-29) accelerated linear growth: first-year height velocity rose from about 4.1 cm/year to roughly 7-8 cm/year, without excessive IGF-1 generation ^[1].

In healthy older men (mean age 68), subcutaneous GHRH(1-29) at 0.5 mg and 1 mg twice daily for fourteen days produced dose-related increases in 24-hour GH and IGF-1; after the high dose, their GH and IGF-1 parameters no longer differed from those of young men, with no change in fasting glucose ^[2]. This men's-health, dose-related IGF-1 story is the lens this site reads sermorelin through — laid out in full on sermorelin and IGF-1.

A stabilized GHRH analog studied in 152 older adults raised IGF-1 by 117% within the physiologic range and had a favorable effect on cognition over twenty weeks ^[6]. That is a finding for the analog class, not a treatment claim for sermorelin — a distinction this digest keeps in view throughout.

How to read this site

Every figure here is carried back to a numbered study you can check on the full reference list. The pages are organized the way the evidence is: sermorelin and IGF-1 for the men's-health GH-axis data, sermorelin vs CJC-1295 for the native-versus-stabilized comparison, the research findings for mechanism and the study-by-study record, and the doses studied in the literature in strict 'studied at X in this population' framing.

What this site is not: a clinic, a pharmacy, or a source of dosing advice. The 'order' in the name is the order of a composed reading of the literature, not a checkout. For the common questions — testosterone, IGF-1, timing, side effects — see the frequently asked questions.