Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of GHRP-6 and Sermorelin — mechanism, side effects, legal status, and pricing.
GHRP-6 is a synthetic hexapeptide (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2) growth hormone secretagogue and ghrelin receptor agonist. Developed by Bowers and Momany and first described in 1984, it was the first synthetic GHRP characterized and is defined by its pronounced appetite-stimulating effect — the strongest of any clinically studied GHRP. It has never been approved by the FDA or any regulatory agency and remains a research-only compound used off-label in the grey market.
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(EMD Serono) for diagnostic testing of pituitary GH reserve and later for pediatric idiopathic GH deficiency, but was withdrawn from the US market in 2008–2009 at the manufacturer's request for commercial reasons (not safety or efficacy).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.
GHRP-6
Sermorelin
Category
Legal Status
Mechanism
Half-life
Side Effects
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
GHRP-6
Sermorelin
COA corpus from Disclosed Labs — independently tested batches only.
GHRP-6
13
COAs
99.4%
Avg purity
4
Labs
Sermorelin
72
COAs
99.4%
Avg purity
10
Labs
GHRP-6 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.
GHRP-6 was first characterized by Bowers, Momany, Reynolds, and Hong in Endocrinology (1984, PMID 6714155), establishing it as the first synthetic peptide to specifically release GH via a non-GHRH mechanism — a key tool in the later discovery of the ghrelin receptor. Ghigo et al. (European Journal of Endocrinology, 1997, PMID 9186261) reviewed the GHRP class and confirmed GH, ACTH/cortisol, and prolactin co-stimulation in humans. Berlanga et al. (Clinical Science, 2007, PMID 16989643) demonstrated ~78% infarct-mass reduction in a porcine myocardial infarction model via antioxidant mechanisms, and Berlanga-Acosta et al. (Clinical Medicine Insights: Cardiology, 2017, PMID 28469491) reviewed the cytoprotective GHRP literature across cardiac, neuronal, and hepatic tissues. GHRP-6 has never been approved for any clinical indication; its intense appetite stimulation and cortisol/prolactin co-release limit its clinical utility compared with ipamorelin.
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.
GHRP-6 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.
Contraindications
Lab Testing
Key references
Disclosed Labs