Underground Biohacking
Growth hormone

Sermorelin

Chris Hallewell, founder of Underground Biohacking

By , Founder, Underground Biohacking

Last reviewed

Prescription only

Sermorelin is a synthetic copy of the first 29 amino acids of growth hormone releasing hormone (GHRH). It tells your pituitary gland to release its own growth hormone. Real clinical evidence exists, but nearly all of it is in children with growth hormone deficiency. Two small trials in older adults found modest changes. No trial has tested it for anti ageing, fat loss or muscle gain in healthy adults. It was once an approved US medicine. It is not one today.

What is Sermorelin?

Sermorelin is a growth hormone releasing hormone analogue. Your hypothalamus, a control centre at the base of the brain, makes natural GHRH. That natural hormone is 44 amino acids long. Sermorelin copies only the first 29 of them. Those 29 carry the full signal. A 1999 drug review called sermorelin the shortest synthetic peptide with full biological activity of GHRH. Because it is a copy of a natural signal, sermorelin does not act like injected growth hormone. It does not add hormone to your blood. It knocks on the pituitary gland instead. The pituitary then releases growth hormone in its own pulses. Your body's normal brakes, mainly a hormone called somatostatin, still apply. That is the theoretical safety argument for this class. Sermorelin is not a research chemical with no history. It was a licensed medicine in the United States for years. Doctors used it to test whether a child's pituitary could make growth hormone. It was later approved to treat some children who were growing too slowly. It sits in the same family as tesamorelin and CJC-1295.

What is Sermorelin prescribed for?

  • In children with growth hormone deficiency, average growth rate rose from about 4 cm a year to 8 cm after six months.[1]Human study
  • In nine children whose growth hormone deficiency followed brain radiotherapy, growth rate rose from 3.3 to 6.0 cm a year.[3]Human study
  • Across the published trial data, sermorelin produced catch up growth in most children with growth hormone deficiency.[6]Human study
  • In five children with short stature, an intranasal dose raised growth hormone, peaking at 15 minutes in every child.[8]Human study
  • In 19 healthy older adults, overnight growth hormone output and IGF-1 both rose within four weeks.[5]Human study
  • In older men and women, skin thickness rose in both sexes and lean body mass rose in the men only.[4]Human study
  • In a review of records from 14 men, IGF-1 rose while they took sermorelin with two other peptides.[7]Human study

How does Sermorelin work?

Sermorelin copies the first 29 amino acids of GHRH, your own growth hormone releasing hormone. Those 29 carry the full signal. Tests found the short copy works as well as the full length hormone. It knocks on the GHRH receptor on somatotroph cells, the growth hormone factory in your pituitary gland. That prompts the gland to make and release its own growth hormone in pulses. It does not add growth hormone to your blood from outside. Your normal controls still apply. Somatostatin, the body's brake hormone, damps the response. Growth hormone then drives IGF-1 output in the liver.

Educational reference only. Talk to a licensed clinician for any decisions on Sermorelin.

What are the side effects of Sermorelin?

EffectHow seriousWhat to watch
Facial flushing and pain where the injection went in were the most common problems in the approved product's trials.[6]Mild and short livedWarmth or redness in the face, and soreness at the injection site.
Antibodies against GHRH appeared in 14 of 18 treated children, though they did not appear to blunt the response.[2]Unclear meaningA response that fades after a good start.
Four children in that same study grew more slowly on the drug, and the authors could not explain why.[2]UnexplainedGrowth rate compared with the year before treatment started.
In the older adult trial, the only side effect recorded was a temporary rise in blood lipids.[4]Mild, resolved on its ownA lipid panel if treatment runs for months.
The uses that drive current peptide demand have not been tested in clinical trials, so the risks are unmeasured.[9]UnknownNothing specific, because nobody has studied it.

Is Sermorelin legal in 2026?

Checked 6 August 2026. Sermorelin has a real FDA history. GEREF (sermorelin acetate) was approved on 28 December 1990 for testing whether the pituitary can release growth hormone. A second GEREF product was approved on 26 September 1997 to treat idiopathic growth hormone deficiency in children with growth failure. EMD Serono discontinued both products in 2008. FDA withdrew both approvals with effect from 18 June 2009. In 2013 FDA determined that neither was withdrawn for reasons of safety or effectiveness. No FDA approved sermorelin product is marketed in the United States today. It is also not one of the six substances on FDA's 503A bulks list.

Status checked against the primary source.

Educational reference only. Talk to a licensed clinician for any decisions on Sermorelin.

If you are considering Sermorelin

This page does not provide dosing, cycling, stacking, or sourcing guidance for Sermorelin. The protocol conversation belongs with a licensed clinician who can review your bloodwork, history, and goals.

Where to buy Sermorelin

Running Sermorelin in your next protocol cycle?

Check out our recommended sources list to find vetted vendors you can trust.

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Frequently Asked Questions

Is sermorelin FDA approved?
Not any more. Two GEREF sermorelin products held FDA approval. One was approved in December 1990 as a pituitary function test. The other was approved in September 1997 to treat growth hormone deficiency in children. The maker discontinued both in 2008, and FDA withdrew the approvals in June 2009. FDA later determined that neither was withdrawn for safety or effectiveness reasons. So it was approved once, and it is not approved now.
What does sermorelin actually do in the body?
It signals your pituitary gland to release growth hormone. Your hypothalamus normally sends that signal using a 44 amino acid hormone called GHRH. Sermorelin copies the first 29 amino acids, which carry the whole message. Because the pituitary does the releasing, hormone still comes out in natural pulses, and your body's own brakes still work. That is the theory behind the class. Whether it changes how you feel is a separate question.
Does sermorelin help with anti ageing, fat loss or muscle?
There is no trial that answers this in healthy adults. The closest evidence is a five month trial in 19 people aged 55 to 71. Skin thickness increased in both sexes. Lean body mass rose in the men only, and body fat did not shift. A 2026 review of peptides used for recovery and performance found the same gap: promising laboratory work, no clinical trials. The honest answer is that nobody knows.
What are the known risks?
From the approved product's trials, the common problems were mild. Facial flushing and pain at the injection site topped the list. Antibodies to GHRH appeared in most treated children, but did not seem to harm their growth. In older adults the only recorded side effect was a temporary rise in blood lipids. What nobody knows is the risk of long term use in healthy adults, because that has never been studied.
What should I ask a doctor about it?
Ask what problem it is meant to solve, and how that problem would be measured. Ask whether a growth hormone deficiency has actually been diagnosed, and by which test. Ask who made the product and what testing it has been through, given that no approved version exists. Ask what would count as it not working, and when you would stop. Ask what gets monitored, including blood sugar and blood lipids.
Is sermorelin banned in sport?
Yes. The World Anti Doping Agency prohibits growth hormone releasing hormone and its synthetic analogues, and sermorelin is one of them. Anti doping laboratories have built mass spectrometry methods to detect sermorelin and its breakdown products in urine. Detection was historically difficult because the amounts reaching urine are very small. That is changing. If you compete under anti doping rules, treat this as a failed test waiting to happen.

References

  1. 1.Thorner M, et al. (1996). Once daily subcutaneous growth hormone-releasing hormone therapy accelerates growth in growth hormone-deficient children during the first year of therapy. Geref International Study Group. The Journal of clinical endocrinology and metabolism. PMID: 8772599. DOI: 10.1210/jcem.81.3.8772599.
  2. 2.Ross RJ, et al. (1987). Treatment of growth-hormone deficiency with growth-hormone-releasing hormone. Lancet (London, England). PMID: 2879138. DOI: 10.1016/s0140-6736(87)90699-4.
  3. 3.Ogilvy-Stuart AL, et al. (1997). Treatment of radiation-induced growth hormone deficiency with growth hormone-releasing hormone. Clinical endocrinology. PMID: 9231053. DOI: 10.1046/j.1365-2265.1997.1790998.x.
  4. 4.Khorram O, et al. (1997). Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and women. The Journal of clinical endocrinology and metabolism. PMID: 9141536. DOI: 10.1210/jcem.82.5.3943.
  5. 5.Khorram O, et al. (1997). Effects of [norleucine27]growth hormone-releasing hormone (GHRH) (1-29)-NH2 administration on the immune system of aging men and women. The Journal of clinical endocrinology and metabolism. PMID: 9360512. DOI: 10.1210/jcem.82.11.4363.
  6. 6.Prakash A, Goa KL (1999). Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy. PMID: 18031173. DOI: 10.2165/00063030-199912020-00007.
  7. 7.Sigalos JT, et al. (2017). Growth Hormone Secretagogue Treatment in Hypogonadal Men Raises Serum Insulin-Like Growth Factor-1 Levels. American journal of men's health. PMID: 28830317. DOI: 10.1177/1557988317718662.
  8. 8.Borkenstein M (1986). The effects of intranasal insufflation of growth hormone releasing factor analogue GRF 1-29 NH2 on growth hormone secretion in children with short stature. Acta endocrinologica. Supplementum. PMID: 2877535. DOI: 10.1530/acta.0.112s135.
  9. 9.Rahman OF, et al. (2026). Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions. Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews. PMID: 41490200. DOI: 10.5435/JAAOSGlobal-D-25-00236.
  10. 10.Memdouh S, et al. (2021). Advances in the detection of growth hormone releasing hormone synthetic analogs. Drug testing and analysis. PMID: 34665524. DOI: 10.1002/dta.3183.

One more time, because it matters

This page exists to identify Sermorelin and explain what the research describes. Underground Biohacking does not advise on dosage, cycling, stacking, or where to source prescription compounds. If Sermorelin is part of your plan, that conversation belongs with a clinician who can review your labs, history, and goals. Not with a website.