Verified July 2026 · Cited to primary sources

Hexarelin: Evidence Grade D. Animal studies only, unproven in humans.

Grade DResearch-onlySafety: amber

The honest verdict

The most scientifically interesting GHRP thanks to a real, human, GH-independent cardiac effect, but 'interesting mechanism' is not 'proven benefit.' No trial shows it builds muscle, its GH effect fades with repeat dosing, and it is research-only. Grades D for the use case people actually search.

Hexarelin at a glance

Class
Growth hormone secretagogue (ghrelin/GHS-R1a agonist, hexapeptide) with a separate cardiac (CD36) action
Mechanism
Agonist at the ghrelin receptor (GHS-R1a) that triggers pituitary GH release. Uniquely, it also acts on the cardiac scavenger receptor CD36, and human studies show an acute, short-lasting positive inotropic effect (better left-ventricular ejection fraction) that is independent of GH. The catch for GH use is desensitization: repeated dosing blunts the GH response (tachyphylaxis), so the hormonal effect fades.
Also known as
Examorelin, EP-23905, His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2
Research applications
  • Cardiac function / inotropy research (GH-independent, via CD36)
  • Growth hormone stimulation research
  • Preclinical cardioprotection after myocardial infarction
Forms
Lyophilized powder for reconstitution (research supply), Subcutaneous injection (research use)
Legal status
Research-only
WADA (anti-doping)
Prohibited at all times (S2.2.4, GH-releasing peptides), examorelin (hexarelin) named on the WADA Prohibited List
Evidence grade
Grade DAnimal studies only, unproven in humans

How we grade evidence

Every grade comes from a fixed A to F rubric: human-trial strength, not hype or affiliate status. Last verified July 6, 2026.

What is Hexarelin?

The GHRP with the most interesting side story: beyond releasing GH it has a direct, GH-independent positive effect on heart contractility in humans via a cardiac receptor. That cardiac finding is real and human. What is missing is any trial showing it does the muscle-building it is sold for, plus it loses its GH punch fast with repeat dosing.

Agonist at the ghrelin receptor (GHS-R1a) that triggers pituitary GH release. Uniquely, it also acts on the cardiac scavenger receptor CD36, and human studies show an acute, short-lasting positive inotropic effect (better left-ventricular ejection fraction) that is independent of GH. The catch for GH use is desensitization: repeated dosing blunts the GH response (tachyphylaxis), so the hormonal effect fades.

How strong is the evidence for Hexarelin?

Hexarelin has legitimate human pharmacology data, including a distinctive controlled finding that it acutely improves cardiac ejection fraction independent of GH (Bisi 1999, both in healthy controls and in hypopituitary adults). But these are acute mechanism studies, not efficacy trials. There is no randomized controlled trial showing it builds muscle, improves body composition, or treats a cardiac condition over time, and its GH effect is undermined by tachyphylaxis. Real human data, no proven clinical benefit for any marketed use, so D.

Primary sources (3)

  1. Bisi 1999, J Endocrinol Invest, acute cardiovascular and hormonal effects of hexarelin in humans; short-lasting positive inotropic effect, GH-independent
  2. Bisi 1999, Eur J Pharmacol, cardiac effects of hexarelin in hypopituitary adults (raised LVEF without BP/HR change, GH-independent)
  3. WADA Prohibited List, GH-releasing peptides incl. examorelin (hexarelin) banned at all times (S2.2.4)

What is Hexarelin used for?

Hexarelin is marketed for the goals below. See how it ranks against other peptides in each, by evidence, not hype.

Best peptides for Muscle Growth →

What does Hexarelin cost, and how do you access it legally?

Typical cost

UNKNOWN

No FDA-approved or compoundable route, so no legitimate price exists. Research chemical only, which we do not price.

No legal supervised access route right now.

Hexarelin has no compliant US route today. Vials sold "for research use only" are a gray-market fig-leaf, not a legal loophole, so we don't link them. If you pursue Hexarelin, do it with a licensed clinician, and re-check its legal status first.

Is Hexarelinsafe? Side effects & risks

Limited human safety data, no major documented harms

Not FDA-approved and not compoundable; sold only as a research chemical. Human dosing in studies was short-term and acute, so chronic-use safety is unknown. Of the GHRPs, hexarelin is notable for tachyphylaxis (the GH response drops with repeated dosing) and for raising cortisol and prolactin. Its direct cardiac action is a double-edged sword: interesting for research, unstudied for safety in ongoing self-use. Class risks of sustained GH elevation apply (water retention, joint aches). Unregulated supply is the practical danger: roughly 40% of tested online/compounded peptides were mislabeled per FDA.

Medical disclaimer: This page is independent editorial information, not medical advice, and Best Peptide For That is not a medical provider. We do not provide dosing. Talk to a licensed clinician before starting, stopping, or changing any peptide or medication. Full medical disclaimer.

FAQ

Hexarelin FAQ

What makes hexarelin different from the other GHRPs?

Beyond releasing growth hormone, it acts on the cardiac receptor CD36 and has shown an acute, GH-independent positive effect on heart contractility in humans. That cardiac action is unique in this class, though it has not been developed into an approved therapy.

Does hexarelin lose effectiveness over time?

For GH release, yes. Hexarelin is well known for tachyphylaxis: the growth-hormone response is blunted with repeated dosing. That desensitization is one reason it never became a practical long-term GH therapy.

Is hexarelin approved or legal to compound?

No. It is not FDA-approved and cannot be legally compounded. It is sold only as a research chemical and is banned in sport at all times under WADA S2.2.4.

Does hexarelin build muscle?

There is no human trial showing that. It raises GH acutely and has a cardiac effect, but no controlled study has measured muscle, strength or body composition from its use, which is why it grades D.

From our portfolio

Tracking Hexarelin?

Titrate is an iOS app for logging doses, schedules and progress over time, with a reconstitution calculator built in. It tracks, it does not prescribe.

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How we grade the evidence →Are peptides safe? →FDA peptide status 2026 →

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