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Hexarelin: quick citable summary
Hexarelin is listed by PeptaHub as a muscle & growth peptide with a research only legal-status classification. The page summarizes mechanism, research context, common routes, safety notes, and references for writers and AI answer engines.
PeptaHub. “Hexarelin: Mechanism, Research Context, Safety.” peptahub.com, 2026. https://peptahub.com/peptides/hexarelin. Licensed CC BY 4.0.
License: Creative Commons Attribution 4.0 International. Link back to https://peptahub.com/peptides/hexarelin.
What is Hexarelin?
Hexarelin is a potent GHRP acting at the ghrelin receptor. It also acts on the heart via CD36: one small study in 24 bypass-surgery patients found acute, non-GH-mediated improvement in cardiac performance. There are no heart failure or cardiovascular outcome trials.
Overview
Hexarelin is one of the most potent synthetic growth hormone releasing peptides (GHRPs), producing the strongest GH release of any GHRP. It is a hexapeptide analog of GHRP-6 with a methylated tryptophan residue. Beyond GH release, it acts directly on cardiac tissue independently of GH, an effect shown acutely in one small study of coronary artery disease patients and in rodent ischemia-reperfusion models.
Mechanism of action
Hexarelin binds to the ghrelin receptor (GHS-R1a) in the pituitary and hypothalamus, stimulating robust GH release. It also acts on the heart, where CD36 rather than GHS-R1a has been identified as the receptor mediating its cardioprotective effects. In rats, hexarelin protected cardiomyocytes from in vivo ischemia-reperfusion injury through interleukin-1 signalling. Unlike Ipamorelin, hexarelin also raises cortisol and prolactin.
Reported study ranges
| Purpose | Route | Reported range | Frequency | Notes |
|---|---|---|---|---|
| GH release / body composition | subcutaneous | 100–200 mcg | 2-3x daily | Inject on empty stomach. GH response desensitizes with continuous use — cycle 4-8 weeks on, 4 weeks off. Keep doses moderate to limit cortisol/prolactin effects. |
Reported ranges are for research context only. Consult a qualified healthcare professional before using any peptide.
Convert Hexarelin research-range units
Need to convert mg to mcg, dose volume, or U-100 syringe units? The Hexarelin dose calculator is preloaded with these ranges, or use the general dose unit converter.
Research summary
Hexarelin is a potent GH secretagogue in animals and humans, though no published trial establishes a specific fold-increase over baseline at the doses used in community protocols. Its cardiac effects have been studied in one small human study: 24 men with coronary artery disease undergoing bypass surgery received a single 2 mcg/kg intravenous dose and showed prompt increases in left ventricular ejection fraction, cardiac index and cardiac output plus reduced wedge pressure. GHRH and recombinant GH produced no such effect, indicating the response is not GH-mediated (Broglio, Eur J Pharmacol 2002). There are no heart failure trials and no cardiovascular outcome trials. Preclinical work in rats shows protection from ischemia-reperfusion injury. Tachyphylaxis with sustained GH secretagogue dosing is described in the class literature. Reported side effects include cortisol and prolactin elevation, appetite stimulation, and water retention.[1][2][3][4][5]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Hexarelin for synergistic effects.
Legal status
Not FDA-approved for any indication and not approved anywhere. It was investigated clinically in the 1990s and 2000s, mainly as a GH secretagogue and in acute cardiac studies, and is now sold as a research peptide. Not a scheduled substance. Verify current federal and state rules before relying on access claims.
Sourcing & access
Research compound
Hexarelin is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).
Frequently asked questions
Hexarelin (Examorelin) is a synthetic hexapeptide growth hormone releasing peptide and one of the more potent GHRPs. It also has direct cardiac effects that are independent of growth hormone, mediated through the CD36 receptor.
Hexarelin is described as the more potent GH releaser but, unlike Ipamorelin, it also raises cortisol and prolactin. No published head-to-head trial quantifies the difference in GH output between the two, so the fold-increase figures circulated in community sources are not sourced.
The human evidence is one small study: 24 men with coronary artery disease undergoing bypass surgery received a single 2 mcg/kg intravenous dose and showed a prompt rise in ejection fraction, cardiac index and cardiac output, and a fall in wedge pressure. GHRH and recombinant GH did not do this, so the effect is not GH-mediated. There have been no heart failure trials, and no trials of repeated dosing or clinical outcomes.
Attenuation of the GH response with sustained dosing is described for growth hormone secretagogues as a class. No published hexarelin study defines the time course, so the 4-to-8-weeks-on, 4-weeks-off cycling used in community protocols is a convention rather than a trial-derived schedule.
Community protocols use 100 to 200 mcg injected subcutaneously 2 to 3 times daily on an empty stomach. These are user-reported ranges, not trial-derived: the published human hexarelin work used single intravenous doses. Cortisol and prolactin elevation is a documented effect of hexarelin, and cycling is a community convention intended to limit receptor desensitization.
Research references
- The cardiovascular action of hexarelinReview
- Effects of acute hexarelin administration on cardiac performance in patients with coronary artery disease during by-pass surgeryPubMed
- The Growth Hormone Secretagogue Hexarelin Protects Rat Cardiomyocytes From in vivo Ischemia/Reperfusion Injury Through Interleukin-1 Signaling PathwayPubMed
- Mechanism of action of Hexarelin. I. Growth hormone-releasing activity in the ratPubMed
- The Safety and Efficacy of Growth Hormone SecretagoguesPubMed