Ipamorelin and sermorelin are sold side by side, prescribed side by side and compared constantly, and the comparison usually skips the one thing that separates them most: their paper trails. Sermorelin carried FDA approval from 1990, first as a diagnostic and from 1997 as a pediatric treatment, until 2009. Ipamorelin never had one, and its human trials were intravenous studies of how quickly the gut restarts after bowel surgery. This page puts the two records next to each other. It is a table, not a verdict, and it recommends neither. How brands appear on this site is set out on our disclosure page.
Two receptors, one hormone
Sermorelin is GHRH(1-29)-NH2, the active fragment of growth hormone-releasing hormone, and acts on the pituitary's GHRH receptor (Prakash and Goa 1999). Ipamorelin is a five-residue synthetic peptide, Aib-His-D-2-Nal-D-Phe-Lys-NH2, that acts on the growth hormone secretagogue receptor — the receptor ghrelin uses. Novo Nordisk's scientists called it "the first selective growth hormone secretagogue" in 1998 because, in their animal work, it released growth hormone without the rise in cortisol and ACTH that GHRP-6 and GHRP-2 produced (Raun et al., Eur J Endocrinol). That selectivity claim comes from rats and pigs; it is the reason ipamorelin is marketed as the "clean" secretagogue.
The two records, side by side
| Sermorelin | Ipamorelin | |
|---|---|---|
| What it is | GHRH(1-29)-NH2, 29 residues | Synthetic pentapeptide |
| Receptor | GHRH receptor | Ghrelin receptor (GHS-R1a) |
| US approval | GEREF, NDA 019863 (approved 1990-12-28) and NDA 020443 (approved 1997-09-26), both Discontinued; FDA determined the withdrawal was not for safety or effectiveness | Never approved |
| Labelled dose | Pediatric only: about 30 micrograms per kilogram once nightly, subcutaneous | None |
| Registered treatment trials (ClinicalTrials.gov, 2026-09-23) | Zero. Three records name it, all as a 1 microgram per kilogram intravenous diagnostic test | Two, both Helsinn, both intravenous, both in bowel-resection patients |
| Largest human trial | Pediatric treatment programme (label); adults: 11 men on 2 mg nightly (Vittone 1997) | 117 surgery patients, 0.03 mg per kilogram IV twice daily (Beck 2014); a 320-patient follow-on has no posted results |
| Adult doses on record | 0.5 to 1 mg twice daily; 2 mg once nightly | 0.03 mg per kilogram IV twice daily; 4.21 to 140.45 nmol per kilogram single infusions |
| Half-life | Minutes; GH stays raised about 3 hours after IV (Wilton 1993) | About 2 hours, terminal (Gobburu 1999) |
| Adverse events recorded | Transient facial flushing and injection-site pain most common (pediatric review) | 87.5% any event on ipamorelin vs 94.8% on placebo, post-surgery |
| Compounding status | Compoundable on the 2013 not-for-safety determination | FDA category 2 for 503B, immunogenicity cited |
| WADA 2026 | Prohibited at all times (GHRH analogue) | Prohibited at all times (growth hormone secretagogue) |
What each trial actually tested
Sermorelin. The adult evidence is three small trials in older people. At the National Institute on Aging, 10 men around 68 received 0.5 mg and 1 mg twice daily for two weeks each; only the higher dose raised GH and IGF-I significantly (Corpas 1992). At Johns Hopkins, 11 men aged 64 to 76 self-injected 2 mg once nightly for six weeks; nocturnal GH rose, IGF-I did not (Vittone 1997). The figures compounding pharmacies now state — 200 to 300 micrograms nightly — sit well below both. The full breakdown is on our sermorelin dosage page.
Ipamorelin. The human record is pharmacology plus surgery. Healthy men received single 15-minute infusions across a 33-fold range, and every dose produced one pulse of growth hormone peaking at about 40 minutes (Gobburu 1999). Then Helsinn tested it as a gut-motility drug: 117 patients after bowel resection received 0.03 mg per kilogram intravenously twice daily for up to seven days. Median time to a tolerated solid meal was 25.3 hours against 32.6 on placebo, p = 0.15, and the authors reported no significant difference on any efficacy analysis (Beck 2014). Nothing in that record is a growth hormone outcome in healthy adults, and nothing is subcutaneous. The clinic figures for ipamorelin, usually sold paired with CJC-1295, are on our CJC-1295 and ipamorelin dosage page.
Can they be combined?
As a matter of record: the combination has never been tested. No registered trial gives both, and no indexed study does. The marketing rationale — two receptors, so a larger pulse — draws on stimulation studies that paired GHRH with other ghrelin-receptor peptides in single intravenous doses, such as GHRP-2 (Tiulpakov 1995). Those studies show what happens to growth hormone over a few hours in a clinic. They say nothing about what repeated nightly injections of this particular pair do over months. How this site treats every named blend is set out in peptide stacks explained.
A registry search result that is not a trial
A ClinicalTrials.gov intervention search for ipamorelin returns three records, not two. The third, NCT07717866, is an observational study of ibogaine, 5-MeO-DMT and magnetic e-resonance therapy in special-operations veterans; its "physiological supplementation" arm lists hormones and supplements including gonadorelin. A registry search returns records that mention a compound, not trials of it. Counting three would overstate ipamorelin's registered record by half.
What neither record contains
A head-to-head comparison; a trial in healthy adults under sixty; a subcutaneous ipamorelin trial of any length; a long-term safety study of either; and any outcome beyond hormone levels and short-term strength in older men. The tesamorelin side of the same comparison — a GHRH analogue with a current label — is on our tesamorelin dosage page. Nothing here is a recommendation. The same comparison against tesamorelin, which unlike sermorelin still carries a current label, is on our tesamorelin and ipamorelin side-by-side.
Sources and dates
Read 2026-09-23: Drugs@FDA records for NDA 019863 and NDA 020443 via openFDA; ClinicalTrials.gov v2 records NCT00672074, NCT01280344 and NCT07717866, and the sermorelin search; PubMed abstracts for Raun 1998 (PMID 9849822), Gobburu 1999 (PMID 10496658), Beck 2014 (PMID 25331030), Prakash and Goa 1999 (PMID 18031173), Corpas 1992 (PMID 1379256), Vittone 1997 (PMID 9005976), Wilton 1993 (PMID 8329825) and Tiulpakov 1995 (PMID 7586605). WADA status as recorded on our CJC-1295 and tesamorelin pages from the 2026 Prohibited List. Corrections go to the contact page.