Sermorelin: the basics
What is it?
A lab-made copy of the first 29 building blocks of GHRH, the brain hormone that tells the pituitary gland to release growth hormone.
Research paper 1 ↗Research paper 2 ↗Research paper 3 ↗What do people claim it helps with?
Clinics and websites promote it for anti-aging, muscle, fat loss, sleep and recovery. Those uses were never approved and have not been proven in good trials.
What has research actually shown?
In the 1990s it helped some children with growth hormone deficiency grow faster, though less than growth hormone itself. In small studies of older men it raised hormone levels for a short time.
Research paper 1 ↗Research paper 2 ↗Research paper 3 ↗Has this been demonstrated in people?
Human studies exist, mostly from the 1990s: pediatric trials without long follow-up and a few small, short studies in older adults. No large modern trials test the adult uses people promote.
Research paper 1 ↗Research paper 2 ↗Research paper 3 ↗What side effects, risks and unknowns should I understand?
In children, flushing of the face and pain where it was injected were the most common reported effects. Long-term effects of raising growth hormone in healthy adults are not known.
Research paper 1 ↗Research paper 2 ↗Is it an approved medicine?
Not currently. FDA approved it as Geref in 1990 and 1997, but the maker stopped selling it in 2008. FDA says that was not for safety or effectiveness reasons. Today no FDA-approved sermorelin product is sold in the U.S.
FDA safety information 1 ↗FDA safety information 2 ↗FDA briefing 3 ↗Approval here means U.S. FDA approval and applies to a particular product, formulation and use. This is a starting overview, not a complete side-effect list. Sources checked 10 October 2026; independent scientific review pending.
How is it used or studied?
Was an injectable prescription product (Geref). Any sermorelin offered today is compounded or sold as a research chemical, not an FDA-approved product.
Different routes and formulations can have different effects. A study of one product does not validate every product with the same peptide name.
A common misunderstanding
Past FDA approval for children with growth hormone deficiency does not mean it was ever approved or proven for adult anti-aging or bodybuilding use.
What should I ask a clinician?
- What diagnosis or goal are we trying to address, and what established options are available?
- Was the expected benefit shown in people like me, using this exact product?
- How could my medicines, health conditions or pregnancy plans affect the risks?
- What monitoring is needed, and what would tell us the treatment is helping or should be stopped?
What do the research words mean?
- Peptide
- A short chain of amino acids, the building blocks of proteins.
- Preclinical
- Research in cells, tissues or animals before dependable treatment evidence in people.
- Controlled trial
- A study comparing a treatment with another treatment or a placebo to help separate its effects from other explanations.
- Biomarker
- A measurement, such as a hormone level. A change does not necessarily mean someone feels better or lives longer.
Sermorelin Evidence & Clinical Profile
Human Study Limits
Sermorelin has been investigated in clinical contexts. Patient outcomes must be evaluated against study size, design, and control cohorts.
Laboratory & In Vivo Assays
Cellular and animal disease models examine receptor binding affinities and signaling cascades, which require human confirmation.
What is Sermorelin?
Sermorelin Acetate (formerly Geref) is Sermorelin is the first 29 amino acids of human growth hormone-releasing hormone (GHRH). FDA approved it as Geref for a pituitary diagnostic test (1990) and for growth failure in children with idiopathic GH deficiency (1997). The manufacturer discontinued both products in 2008, and FDA later found the withdrawal was not for safety or effectiveness reasons. No FDA-approved sermorelin product is marketed in the U.S. today. Aliases include: Geref, GHRH(1-29)NH2, GRF(1-29)NH2, Groliberin.
- Sequence (one-letter)
- YADAIFTNSYRKVLGQLSARKLLQDIMSR-NH2
- Molecular formula
- C149H246N44O42S
- Molecular weight
- 3357.9 g/mol
- CAS Number
- 86168-78-7
- UNII Code
- 89243S03TE
- PubChem CID
- 16132413
Identifiers checked against PubChem and FDA's Global Substance Registration System on 13 October 2026. FDA substance record ↗ · PubChem record ↗ See all names and codes in the peptide name index.
Clinical Trials & Human Cohorts
Human research can examine tolerability, symptoms or patient outcomes. The design and comparator determine what each result can establish.
Once daily subcutaneous GHRH therapy accelerates growth in GH-deficient children during the first year of therapy [1]
What was reported
Average height velocity roughly doubled over the first 6 months and stayed raised at 12 months, without excess bone-age advance or adverse laboratory changes.
What limits the conclusion
No control group and only one year of follow-up; final adult height was not reported. The study was run by the Geref International Study Group.
Growth response to growth hormone-releasing hormone(1-29)-NH2 compared with growth hormone [2]
What was reported
Most children grew faster on GHRH(1-29). Growth with the lower GHRH regimen was the slowest, and only the GH-treated group improved height relative to bone age.
What limits the conclusion
Small, six-month study. It suggests sermorelin is not superior to growth hormone itself.
GH-releasing hormone-(1-29) twice daily reverses the decreased GH and IGF-I levels in old men [3]
What was reported
Over 14 days, the higher regimen raised 24-hour GH and IGF-I in older men to levels similar to young men. Glucose and blood pressure did not change.
What limits the conclusion
Hormone levels only, over two weeks. No body-composition, strength or clinical outcomes were tested.
Effects of single nightly injections of GHRH (GHRH 1-29) in healthy elderly men [4]
What was reported
Night-time GH release rose, but IGF-I did not. Two of six strength measures improved; body composition did not change.
What limits the conclusion
No placebo group, 11 participants and multiple outcomes tested. The authors judged this regimen less effective than repeated daily dosing.
How the compound may work
Mechanisms describe how Sermorelin may affect biological processes. Laboratory findings and patient outcomes answer different questions.
Pituitary GHRH receptor agonism
Sermorelin binds the GHRH receptor on pituitary somatotroph cells and triggers growth hormone release. Because it works through the pituitary, GH output is still limited by somatostatin and IGF-I feedback. [5]
Diagnostic use of the GH response
A brief GH rise after intravenous sermorelin shows that the pituitary can secrete GH. A normal response cannot rule out deficiency caused by the hypothalamus, so it was used alongside other tests. [5]
Areas Being Studied
These research topics reflect active areas of scientific exploration, distinct from unverified commercial marketing claims.
Pediatric GH deficiency
Growth velocity in prepubertal children with idiopathic GH deficiency; the basis of the 1997 approval. [1]
Adult GH deficiency testing
GHRH (as Geref) combined with arginine as a provocative test for adult GH deficiency. [11]
Age-related GH decline
Short-term hormone and strength measures in older men; clinical anti-aging benefit is unproven. [3]
Compare the study designs.
| Study | Design / sample | Outcome type | Key limitation |
|---|---|---|---|
| Pediatric GH deficiency · 1996 [1] | Multicenter open-label study n = 110 |
Clinical endpoint evaluation | No control group and only one year of follow-up; final adult height was not reported. The study was run by the Geref International Study Group. |
| GHRH vs GH in children · 1993 [2] | Randomized three-arm comparison n = 43 |
Clinical endpoint evaluation | Small, six-month study. It suggests sermorelin is not superior to growth hormone itself. |
| Older men, 2 weeks · 1992 [3] | Randomized crossover of two regimens n = 19 |
Clinical endpoint evaluation | Hormone levels only, over two weeks. No body-composition, strength or clinical outcomes were tested. |
| Older men, 6 weeks · 1997 [4] | Uncontrolled before-after study n = 11 |
Clinical endpoint evaluation | No placebo group, 11 participants and multiple outcomes tested. The authors judged this regimen less effective than repeated daily dosing. |
Regulatory Status & Clinical Safety
Regulatory Classification
Geref approvals (NDA 019863 and NDA 020443) were withdrawn at the sponsor's request after 2008 discontinuation; FDA determined in 2013 that this was not for safety or effectiveness reasons. Sermorelin acetate is in FDA's 503B category 1 (under evaluation). WADA S2 prohibited substance.
Safety Realities & Impurities
Safety depends on the molecule, formulation, route and evidence. A laboratory purity measurement alone cannot establish safety for human use.
Clinical Trials Registry Records
Official registry records from ClinicalTrials.gov. Study registration does not imply government endorsement or guaranteed efficacy.
Diagnosing Adult Growth Hormone Deficiency [11]
- Planned enrollment
- 160 (patients)
- Posted results
- Pending in registry
- Sponsor
- Helsinki University Central Hospital
- Last updated
- 2017
Sexually Dimorphic Effects of GHRH in Adult Growth Hormone Testing [12]
- Planned enrollment
- 90 (patients)
- Posted results
- Pending in registry
- Sponsor
- Children's Mercy Hospital Kansas City
- Last updated
- 2010
WADA & Anti-Doping Regulations
WADA Section S2: Prohibited Substance
The World Anti-Doping Agency (WADA) classifies Sermorelin under Section S2 of the Prohibited List. Prohibited at all times (in- and out-of-competition). Last verified: October 2026.
Research Timeline
-
1990
Diagnostic approval
FDA approves Geref (NDA 019863) to test whether the pituitary can secrete GH. [6]
-
1997
Treatment approval
FDA approves Geref (NDA 020443) for growth failure in children with idiopathic GH deficiency. [7]
-
2008
Discontinued
EMD Serono tells FDA both Geref products are being discontinued. FDA withdraws the approvals effective June 2009. [8]
-
2013
FDA determination
FDA concludes Geref was not withdrawn from sale for reasons of safety or effectiveness. [8]
-
2026
Current status
No approved U.S. product. Sermorelin acetate is listed in FDA's 503B bulk-substance category 1 (under evaluation). [9]
-
2026
Banned in sport
WADA's 2026 Prohibited List names sermorelin among GHRH analogues in class S2, banned at all times. [10]
What Researchers Still Don't Know
Long-term safety profiles
Multi-year observational data in broader heterogeneous cohorts remains uncharacterized.
Optimal dose-response thresholds
Comparative trials optimizing minimal effective exposure versus adverse event rates.
Formulation bioavailability
Differences between oral, subcutaneous, and modified peptide delivery vehicles.
References
Primary sources verified against PubMed / NLM and regulatory databases.
- Multicenter open-label trial
- Randomized comparative trial
- Randomized crossover study
- Uncontrolled pilot study
- Drug review
- FDA Drugs@FDA record
- FDA Drugs@FDA record
- Federal Register notice
- FDA compounding list
-
Anti-doping rule
World Anti-Doping Code International Standard: Prohibited List 2026 ↗ (external website)
-
Registry Record
Diagnosing Adult Growth Hormone Deficiency ↗ (external website)
-
Registry Record
Sexually Dimorphic Effects of GHRH in Adult Growth Hormone Testing ↗ (external website)