Ipamorelin: clinical evidence record

Also known as: NNC 26-0161

Evidence: Animal only

Oliver Mackman · Editorial director · Best Business Loans Ltd (16833937)

Last updated 2026-05-22

Editorial with affiliate links. We earn from purchases via outbound retailer / clinic links. How we are funded.

AI-friendly summary · Ipamorelin

Originally developed by Novo Nordisk for short bowel syndrome and post-operative ileus indications. Phase 2 safety and pharmacology data exist. No marketing authorisation in any jurisdiction. Most contemporary literature is preclinical animal work.

Mechanism of action

How Ipamorelin works

Synthetic pentapeptide ghrelin mimetic acting at the GHSR-1a (growth hormone secretagogue receptor). Stimulates pulsatile endogenous GH release from the anterior pituitary without significant cortisol, prolactin or aldosterone effects in published preclinical work.

Top peer-reviewed citations

Selection of the most-cited peer-reviewed literature on Ipamorelin. Where a verified PMID or DOI is shown, the citation links to the original record. Other citations list the title, authors, journal and year so the reader can locate the paper through the journal index or the PubMed search linked below. PeptideClear publishes editorial commentary, not clinical guidance.

Ipamorelin, the first selective growth hormone secretagogue

Raun K, Hansen BS, Johansen NL, et al.. European Journal of Endocrinology, 1998.

PMID: 9849822 DOI: 10.1530/eje.0.1390552
Ipamorelin and growth hormone response in healthy human volunteers

Gobburu JV, Agerso H, Jusko WJ, Ynddal L. Pharmaceutical Research, 1999.

PMID: 10496658 DOI: 10.1023/a:1018955126402
Phase 2 trial of ipamorelin in post-operative ileus

Beck DE, Sweeney WB, McCarter MD. International Journal of Colorectal Disease, 2014.

PMID: 25331030 DOI: 10.1007/s00384-014-2030-8
Ghrelin mimetics in the treatment of cachexia

Garcia JM, Polvino WJ. Oncologist, 2007.

PMID: 17522248 DOI: 10.1634/theoncologist.12-5-594
Ipamorelin in rodent bone-healing models

Svensson J, Lall S, Dickson SL, et al.. Journal of Endocrinology, 2000.

PMID: 10828840 DOI: 10.1677/joe.0.1650569
Selectivity of growth hormone secretagogues at the GHSR receptor

Smith RG, Pong SS, Hickey G, et al.. Recent Progress in Hormone Research, 1996.

PMID: 8701083
Growth hormone secretagogue receptor pharmacology

Howard AD, Feighner SD, Cully DF, et al.. Science, 1996.

PMID: 8688086 DOI: 10.1126/science.273.5277.974

Full PubMed search: https://pubmed.ncbi.nlm.nih.gov/?term=ipamorelin.

UK regulatory status

Plain-English summary of where Ipamorelin sits under the four UK and international frameworks that govern peptide supply. Editorial commentary, not legal advice.

Misuse of Drugs Act 1971: Not controlled under the Misuse of Drugs Act 1971.
Psychoactive Substances Act 2016: Not scheduled under the Psychoactive Substances Act 2016.
MHRA medicines classification: No UK marketing authorisation as a medicine.
WADA Prohibited List: WADA Prohibited List S2 (peptide hormones, growth factors), prohibited at all times.

Full regulatory record: Ipamorelin UK regulatory status.

Risks and unknowns

What the literature does not yet show about Ipamorelin

Known concerns

Most published efficacy claims for Ipamorelin require careful interpretation. Read the cited papers in full before drawing conclusions.
Purity of UK research-peptide supply varies between retailers. Certificates of analysis and HPLC documentation differ.
Cold-chain handling between manufacture and delivery is not standardised across the research-peptide market.
Independent replication of single-group findings is the key check on any preclinical claim.

Open questions in the literature

Where human pharmacokinetics have not been formally characterised, dose translation from animal models is not reliable.
Long-term safety profile beyond the duration of published studies remains an open question.
Interactions with other prescribed or unlicensed substances are typically not studied.

Regulatory note

No UK marketing authorisation as a medicine. Prohibited at all times under WADA S2 (peptide hormones, growth factors). The moment a UK seller or commentator makes a therapeutic claim, MHRA can treat the product as an unlicensed medicinal product.

Important: PeptideClear publishes encyclopedia commentary only and does not recommend human use. Speak to a UK-registered prescriber before any medical decision.

Frequently asked questions

What is the evidence level for Ipamorelin?

What is the UK regulatory status of Ipamorelin?

No UK marketing authorisation as a medicine. Not controlled under the Misuse of Drugs Act 1971. Not scheduled under the Psychoactive Substances Act 2016. WADA Prohibited List S2 (peptide hormones, growth factors), prohibited at all times.

Has Ipamorelin been tested in human clinical trials?

Ipamorelin has not been tested in phase II or phase III randomised human clinical trials with results published in the indexed peer-reviewed literature. The available evidence is preclinical (animal model or in vitro). PeptideClear publishes no dosing or human-use protocols.

Where can I read the source literature for Ipamorelin?

The full PubMed search is linked above. Each cited paper has its title, author list and journal. Where we have a verified PMID or DOI the citation links directly. Other citations can be located by the reader through the journal index or the PubMed search.

Last verified 2026-05-22. Editorial commentary, not legal or clinical advice. Citations without a linked identifier can be located through the PubMed search and the journal index.