Sermorelin
/ser-MOR-eh-lin/aka Geref, GHRH (1-29), GRF 1-29
A once-approved copy of the first 29 amino acids of human GHRH that prompts the pituitary to release its own GH in short pulses.
Sermorelin: educational research discussion. Not medical advice. Not a protocol for you.Details
- Reported range
- 200–300 mcg
- Frequency
- Once nightly
- Cycle length
- Months; nightly or 5 on / 2 off
- Half-life
- ≈ 11–12 min
- Route
- SC
Reported figures describe what is published or discussed. None of them is a dose for you.
Mechanism
What it is proposed to do
Sermorelin is GHRH(1-29)-NH2, the shortest fragment of the natural hormone with full activity. It binds pituitary GHRH receptors and triggers the body's own GH release, which raises IGF-1. It clears in minutes and the pituitary still shapes each pulse, so somatostatin and IGF-1 feedback stay intact. That makes it gentler than injected GH and shorter-acting than tesamorelin or CJC-1295.
- 01
Sermorelin
GHRH(1-29); half-life ~11–12 min
established - 02
Pituitary GHRH receptor
Same receptor as your own GHRH
established - 03
GH pulse ↑ · IGF-1 ↑
Feedback intact; IGF-1 rise depends on dosing frequency
established - 04
Faster growth in GH-deficient children
Shown in pediatric trials; adult benefits unproven
established
Half-life. About 11–12 minutes after IV or SC dosing, per the former Geref label. SC bioavailability was only about 6%. The short GH pulse is the point.
Dosing & cycles
What is reported, and where it comes from
Numbers below are labeled FDA label, clinical trial range or commonly reported range. They describe the published and discussed landscape. They are not instructions and not a protocol for you.
Dosing studio
Every figure is labeled by where it comes from.
Scale view: Older-adult studies
Probe at 1.25 mg: inside the reported band (0.5–2 mg). Drag it to read the scale. It does not pick a number for you.
Typical cycle, as a calendar
Pediatric trial pattern: nightly, continuous
Up to 12 months in trials
One bedtime injection a day, every day. The pivotal pediatric trial measured growth at 6 and 12 months.
Cycle patterns
Pediatric trial pattern: nightly, continuous
One bedtime injection a day, every day. The pivotal pediatric trial measured growth at 6 and 12 months.
Community pattern: 5 on / 2 off
Nightly on weekdays, weekends off. Some clinic protocols run nightly without breaks instead. Neither schedule has adult trial data behind it.
Stacks
What it gets combined with
Why people pair things, and what nobody has tested.
Sermorelin + ipamorelin
2 compounds- Why people combine these
- The older, milder version of the CJC/ipamorelin pair: a GHRH analog to amplify the GH pulse, a ghrelin-receptor agonist to trigger it.
- Caution
- No trial of the pair. Adding a secretagogue adds hunger, fluid-retention and glucose effects.
- What is unknown
- No published human data on this combination: dosing, interactions and long-term effects are all unstudied.
Evidence
How much of this is known
Evidence grade
B
Human RCTs, narrow
Human RCTs exist but are narrow, early, or not for the popular use.
How we gradeGraded B for the pediatric GH-deficiency trials behind its former approval. Adult anti-ageing use has only small, short studies with mixed results.
Human trial status
In a multicenter pediatric trial (110 children with GH deficiency), 30 mcg/kg at bedtime raised growth velocity from 4.1 to 8.0 cm/year at 6 months and 7.2 cm/year at 12 months. In older men, 1 mg twice daily for 14 days restored GH and IGF-1 to young-adult levels (1992). A single nightly 2 mg dose for 6 weeks in 11 older men raised GH but not IGF-1, did not change body composition, and improved 2 of 6 strength measures (1997).
Limitations
- Pediatric GH-deficiency results do not transfer to healthy ageing adults.
- Adult studies are small (about 10–20 people) and short (weeks).
- No trial has tested long-term safety of adult anti-ageing use, including cancer risk.
- Compounded products vary in quality and are not FDA-reviewed.
Sources to read
- Geref International Study Group. Once daily subcutaneous GHRH therapy accelerates growth in GH-deficient children during the first year (JCEM 1996)
- Corpas E et al. GHRH(1-29) twice daily reverses the decreased GH and IGF-I levels in old men (JCEM 1992)
- Vittone J et al. Effects of single nightly injections of GHRH(1-29) in healthy elderly men (Metabolism 1997)
- Prakash A, Goa KL. Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic GH deficiency (BioDrugs 1999)
- Federal Register, March 4, 2013. Determination that GEREF was not withdrawn from sale for reasons of safety or effectiveness
Links open PubMed, DailyMed, FDA or trial-registry searches. We do not cite what we have not described accurately.
Safety
Side effects, cautions, status
Commonly reported effects
- In the pediatric trials behind the Geref approval, about 1 in 6 patients had injection-site pain, swelling or redness. Headache, flushing and dizziness each occurred in under 1%.
- Hypothyroidism appeared in 6.5% of patients in clinical studies.
- Many patients developed anti-GRF antibodies, usually without loss of effect.
- As with any GH-raising compound, water retention and changes in glucose handling are possible.
Who should be extra cautious
- Active or past cancer. Raises GH and IGF-1, a growth signal. No long-term adult safety data in this group.
- Thyroid disease. Hypothyroidism appeared in 6.5% of patients in the Geref clinical studies.
- Diabetes or prediabetes. GH elevation can worsen insulin sensitivity.
- Pregnancy or breastfeeding. No adequate data.
- Tested athletes. Prohibited at all times (WADA S2.2.4, named).
Legal & regulatory status
FDA approved sermorelin as Geref (EMD Serono) for diagnostic testing in 1990 and for idiopathic GH deficiency in children in 1997. EMD Serono discontinued both in 2008, and FDA later determined they were not withdrawn for reasons of safety or effectiveness. No sermorelin product is FDA-approved today. What patients receive is compounded, so the specific product has no FDA review.
2026 compounding context. Sermorelin remains widely dispensed by US 503A compounding pharmacies on prescription. It was not among the peptides FDA's advisory committee reviewed in July 2026. Compounded products are not FDA-approved and are not reviewed by FDA for quality before dispensing.
WADA. Prohibited at all times as a GHRH analogue (S2.2.4). Sermorelin is named on the list.
Storage & handling, high level
The former Geref product was a lyophilized powder with diluent. Compounded versions vary by pharmacy in form and handling. Follow the dispensing label, not a forum.
Reconstitution and injection technique are clinical skills. The reconstitution calculator does arithmetic only.
FAQ
Questions people ask about Sermorelin
Was sermorelin pulled for safety reasons?
How is it different from tesamorelin?
Is it the same as CJC-1295?
Does it work for anti-ageing?
Why is it dosed at night?
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