Last updated: May 18, 2026
What hexarelin is
Hexarelin (also called Examorelin) is a synthetic hexapeptide developed in Italy in the 1990s. Sequence: His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2. The methylated tryptophan provides enzymatic stability that other GHRPs lack.
Mechanism — dual receptor activity
Unlike ipamorelin (selective GHS-R1a), hexarelin activates two distinct receptors:
- GHS-R1a (ghrelin receptor): Triggers GH release from pituitary, similar to other GHRPs
- CD36 scavenger receptor: Mediates direct cardioprotective effects on cardiomyocytes
The dual mechanism is hexarelin’s signature feature — and the source of both its potency and its complications.
GH-releasing potency
In dose-comparison studies, hexarelin produces ~30-40% higher peak GH response than equivalent doses of ipamorelin or GHRP-2. This made it the GHRP of choice for early growth hormone deficiency diagnostic testing.
Cardioprotective effects
Independent of GH release, hexarelin has shown:
- Reduced infarct size in animal models of myocardial infarction
- Preservation of cardiac contractility post-ischemia
- Anti-fibrotic effects on cardiac tissue
These effects occur via CD36 activation and are not blocked by GH receptor antagonists.
Side effect profile
Compared to ipamorelin (the cleanest GHRP):
- Cortisol elevation: ~15-25% above baseline (vs ~5% for ipamorelin)
- Prolactin elevation: ~15-20% above baseline
- Appetite stimulation: mild (less than GHRP-6)
- Receptor desensitization: documented with chronic high-dose use
Research dosing
Reported research-community protocols use 100-200 mcg per dose, 2-3 times daily. Higher doses (>300 mcg) are associated with more pronounced cortisol/prolactin effects without proportional GH benefit.
Why ipamorelin replaced hexarelin in most protocols
For most research and clinical applications, the cleaner profile of ipamorelin (similar GH effect, much less cortisol/prolactin/desensitization) outweighs the slightly higher GH peak that hexarelin produces. Hexarelin remains relevant where the cardioprotective CD36 mechanism is desired.
Is hexarelin stronger than ipamorelin?<br />
For acute GH release, yes — hexarelin produces ~30-40% higher peak GH. But over chronic use, ipamorelin’s clean profile and lack of receptor desensitization typically produce better outcomes.
Why does hexarelin cause cortisol elevation?<br />
The methylated tryptophan structure and dual receptor activity make hexarelin less selective. Cortisol/prolactin elevation is a class effect of older GHRPs reduced by the development of more selective compounds like ipamorelin.
Can hexarelin be used long-term?<br />
Receptor desensitization with chronic high-dose use is documented. Cycling protocols (4 weeks on, 2-4 weeks off) are typical.
Does hexarelin really protect the heart?<br />
Animal cardiac models show consistent benefits via CD36 activation. Human cardioprotection data is limited but the mechanism is well-characterized.