The Sunlight Experiment

Supplement Monograph

Hexarelin

PeptideGh

Hexarelin is a synthetic growth-hormone-releasing hexapeptide (ghrelin-receptor agonist) with potent acute GH release and studied cardiac effects; it is not an approved drug or supplement.

Work in progress Updated July 2026

What Is Hexarelin?

Hexarelin is a synthetic hexapeptide growth-hormone secretagogue — a ghrelin-receptor agonist — known for producing a strong, potent acute release of growth hormone. It belongs to the same GHRP family as GHRP-2 and GHRP-6 but is often described as one of the more potent GH-releasing peptides. Beyond the pituitary, it has drawn research interest for direct effects on the heart. It is used experimentally; it is not an approved medicine or dietary supplement.

Evidence

Hexarelin’s acute cardiovascular and hormonal effects have been examined in humans 1Reference 1Bisi G et al. · 1999Clinical trialAcute cardiovascular and hormonal effects of GH and hexarelin, a synthetic GH-releasing peptide, in humans — human studyView study →, and a distinct line of research reports GH-independent cardiac actions: studies describe a specific cardiac GHRP receptor and cardioprotective effects in animal models of myocardial injury 2Reference 2Locatelli V et al. · 1999AnimalThe growth hormone secretagogue hexarelin improves cardiac function in rats after experimental myocardial infarction — rat studyView study →, plus cardiotropic effects in normal subjects, GH-deficient patients, and patients with dilated cardiomyopathy 3Reference 3Broglio F et al. · 2001Clinical trialGrowth hormone-independent cardiotropic activities of growth hormone-releasing peptides in normal subjects, GH-deficient patients, and dilated cardiomyopathy — human studyView study →. This cardiac-receptor biology is scientifically interesting, but the human data are small and mechanistic rather than large outcome trials, and hexarelin is not an approved cardiac therapy. Its popular use for muscle-building or “anti-ageing” is not supported by a verified clinical outcome trial in this pass; note also that GHRPs in this class tend to show tolerance/attenuation with repeated dosing.

Dosage & Safety

There is no established supplement dose for hexarelin; online regimens are not derived from controlled human efficacy trials, and this page makes no dosing recommendation. Hexarelin is not FDA-approved as a drug or dietary supplement and is prohibited in sport (WADA). It can raise cortisol/prolactin and, given its cardiovascular activity, has unstudied cardiac and blood-pressure implications outside controlled research. Human long-term safety, drug interactions, and pregnancy/lactation safety are not established / not assessed in this pass. Informational only; not an endorsement of use.

References

  1. Bisi G, et al. (1999). Acute cardiovascular and hormonal effects of GH and hexarelin, a synthetic GH-releasing peptide, in humans — human study. J Endocrinol Invest. https://pubmed.ncbi.nlm.nih.gov/10342360/
  2. Locatelli V, et al. (1999). The growth hormone secretagogue hexarelin improves cardiac function in rats after experimental myocardial infarction — rat study. Endocrinology. https://pubmed.ncbi.nlm.nih.gov/10614623/
  3. Broglio F, et al. (2001). Growth hormone-independent cardiotropic activities of growth hormone-releasing peptides in normal subjects, GH-deficient patients, and dilated cardiomyopathy — human study. J Clin Endocrinol Metab. https://pubmed.ncbi.nlm.nih.gov/11322491/