GHRP-6

In simple words

GHRP-6 was the first man-made peptide shown to boost growth hormone release; it also strongly stimulates appetite. It is studied in wasting conditions, and Cuban scientists study it for protecting the heart and healing wounds.

What this molecule is

6 aa: His-D-Trp-Ala-Trp-D-Phe-Lys-NH₂. The first synthetic GHRP (first generation). ~873 Da.

Why it is studied

The first GHRP discovered (1977). A potent orexigenic agent: markedly ↑appetite via the ghrelin receptor. Less GH-selective than GHRP-2: stronger ↑cortisol and ↑prolactin. Cuban studies: cardioprotection, wound regeneration, lung protection. 5 clinical studies 2016–2026. Not approved as a drug anywhere.

How it works

GHS-R1a (ghrelin receptor) → ↑GH. Strong orexigenic effect: activates NPY/AgRP neurons → ↑appetite. Greater ↑cortisol and ↑prolactin than GHRP-2. Cardioprotection: PPARγ → ↓scarring + ↓inflammation. Wound regeneration: via PI3K/mTOR-P70. T½ ~15–20 min (shorter than GHRP-2).

Doses used in studies

Studies used 100–300 mcg SC 2–3 times/day for a course of 4–8 weeks, including in combination with GHRH analogs. In cachexia/anorexia it was considered preferable to ipamorelin (the orexigenic effect is a plus). Research only.

Combined with in studies

• CJC-1295 / Mod-GRF / Sermorelin — GHRH + GHRP synergy
• Ipamorelin — alternative when ↑appetite is undesirable
• GHRP-2 — NOT at the same time: competition for GHS-R1a

Level of evidence

Level B-C Human observational data. There are studies in humans, but they are small, uncontrolled, or cohort studies. The data are encouraging but need confirmation. Clinical studies (Cuban group). Cardiac/renal data come from animals. Not approved as a medicinal product anywhere.

Important to know

Legal status: Russian Federation: not registered as a medicinal product or dietary supplement. Not included in the lists of Government Decree No. 681 (narcotic drugs) or Government Decree No. 964 (potent substances). Research Use Only. US/EU/Australia: unapproved research chemical. WADA: prohibited under S2.2.4, both in and out of competition. ⚠️ Marked ↑appetite: undesirable for weight loss. ↑cortisol and ↑prolactin higher than with GHRP-2. Not approved. Research Use Only. Not a medicinal product or dietary supplement. 🔴 CONTRAINDICATIONS: active cancer • pregnancy • hyperprolactinemia • diabetes mellitus. 🔴 FOR ATHLETES: prohibited by WADA S2.2.4. Use = disqualification. Articles 230.1–230.2 of the Criminal Code of the Russian Federation.

Studies in PubMed

1. Growth hormone releasing peptide-6 (GHRP-6) prevents doxorubicin-induced myocardial and extra-myocardial damages by activating prosurvival mechanisms. (Front Pharmacol, 2024)
2. Growth hormone-releasing peptide 6 prevents cutaneous hypertrophic scarring: early mechanistic data from a proteome study. (Int Wound J, 2018)
3. Growth hormone releasing peptide-6 (GHRP-6) ameliorates acute lung injury and its subsequent evolvement to interstitial fibrosis. (Int Immunopharmacol, 2026)
4. Growth hormone-releasing peptide 6 (GHRP-6) hydrogel for acute kidney injury therapy via metabolic regulation. (J Nanobiotechnology, 2025)
5. Growth Hormone-Releasing Peptide 6 Enhances the Healing Process and Improves the Esthetic Outcome of the Wounds. (Plast Surg Int, 2016)