Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of Ipamorelin and Sermorelin — mechanism, dosing, side effects, legal status, and pricing.
Ipamorelin is a synthetic pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) originally developed by Novo Nordisk and later advanced by Helsinn/Nycomed. It is a selective ghrelin receptor agonist / growth hormone secretagogue (GHRP). Its defining feature versus older GHRPs (GHRP-2, GHRP-6, hexarelin) is that in preclinical and early clinical studies it raised GH without meaningfully increasing ACTH, cortisol, or prolactin. It is not FDA-approved for any indication; a Phase 2 trial for postoperative ileus failed to meet its primary endpoint and clinical development was discontinued. In the wellness/grey market it is sold as a research chemical and used off-label for anti-aging and body-composition goals despite no clinically validated human dose for those uses.
Sermorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) consisting of the first 29 amino acids of the 44-aa native hormone — the shortest fragment that retains full biological activity. It was FDA-approved in the 1990s as Geref (EMD Serono) for diagnostic testing of pituitary GH reserve and later for pediatric idiopathic GH deficiency, but was withdrawn from the US market in 2008–2009 at the manufacturer's request for commercial reasons (not safety or efficacy). It remains on the FDA Category 1 list of bulk substances nominated for use in 503A compounding, where it is now widely prescribed off-label for adult GH insufficiency and "anti-aging" indications.
Ipamorelin
Sermorelin
Category
Legal Status
Mechanism
Dose Range
Route
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
Ipamorelin
Sermorelin
COA corpus from Disclosed Labs — independently tested batches only.
Ipamorelin
153
COAs
99.7%
Avg purity
17
Labs
Sermorelin
72
COAs
99.4%
Avg purity
10
Labs
Ipamorelin and Sermorelin are both among peptides under FDA review for the Category 1 (503A) list; if added, they would require a prescription to be compounded by registered 503A/503B pharmacies — they are not yet authorized. In April 2026 the FDA removed 12 peptides from Category 2, which does not place them on the Category 1 list or authorize compounding. The FDA's Pharmacy Compounding Advisory Committee is advisory and meets July 23–24, 2026 to review nominations and make recommendations to the FDA.
The seminal preclinical characterization (Raun et al., 1998, PMID 9849822) established ipamorelin as the first GHRP-receptor agonist with GH-release selectivity comparable to GHRH, without raising ACTH or cortisol even at doses more than 200-fold above the ED50. Pharmacokinetic-pharmacodynamic modeling in healthy male volunteers (Gobburu et al., 1999, PMID 10496658) confirmed a roughly 2-hour half-life and dose-dependent GH response following IV infusion. The most advanced human study is Beck et al. (2014, PMID 25331030), a Phase 2, randomized, double-blind, placebo-controlled trial in 114 patients after bowel resection evaluating IV ipamorelin 0.03 mg/kg twice daily for postoperative ileus; the drug was well tolerated but did not separate from placebo on the primary endpoint (time to tolerance of solid food), and the sponsor (Helsinn/Nycomed) discontinued development. There are no completed registrational trials in adult GH deficiency, frailty, or body-composition indications. Ipamorelin is not FDA-approved for any indication. The 100–300 mcg dose range reflects community/compounding practice and is not clinically validated for anti-aging or body-composition use.
Key references
Sermorelin was FDA-approved in the 1990s as Geref for the GHRH stimulation test of pituitary function and, at higher doses, for pediatric idiopathic GHD. The principal review of pediatric Geref data is Prakash & Goa (BioDrugs 1999; PMID 18031173). In adults, Vittone et al. (Metabolism 1997; PMID 9005976) showed nightly sermorelin in healthy elderly men raised IGF-1 and modestly increased lean mass, and Khorram, Laughlin & Yen (J Clin Endocrinol Metab 1997; PMID 9141536) demonstrated that 16 weeks of nightly [Nle27]GHRH(1-29) in 19 subjects aged 55-71 restored GH/IGF-1 toward young-adult levels with small gains in lean mass and skin thickness. Walker (Clin Interv Aging 2006; PMID 18046908) reviewed the rationale for sermorelin as a more physiologic alternative to rhGH in adult GH insufficiency. EMD Serono discontinued Geref in 2008; FDA withdrew NDA approvals in 2009 and affirmed in 2013 that this was for commercial — not safety or efficacy — reasons. Unlike exogenous GH, sermorelin has not been associated with reports of acromegaly because endogenous feedback limits peak GH.
Ipamorelin and Sermorelin are both in the Performance category and may have overlapping mechanisms. Researchers should review both profiles carefully, understand the mechanisms of action, and monitor the relevant biomarkers when combining compounds in the same class. As always, consult a licensed healthcare provider before making any decisions about combining research compounds.
This platform provides informational tools only, not medical advice. This comparison is for educational purposes only. Consult a licensed provider.
Frequency
Dosing Notes
Half-life
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Contraindications
Lab Testing
Key references