Hexarelin
Potent GH secretagogue with cardioprotective properties; subject to desensitization.
🔬 Mechanism of Action
Hexarelin is the most potent ghrelin receptor agonist in the GHRP family, producing the strongest GH release pulse. However, it is also the most non-selective, causing significant elevations in cortisol and prolactin. Uniquely, Hexarelin has documented cardioprotective properties — it directly protects cardiac tissue through mechanisms independent of GH release.
The major limitation of Hexarelin is desensitization: continuous use beyond approximately 4 weeks leads to diminishing GH response as receptors downregulate. This necessitates cycling protocols.
Source: PMID: 12165110
📜Background & History
Hexarelin is a synthetic hexapeptide GHRP developed by Europeptides (France) in the 1990s. It is the most potent GHRP known, producing the largest GH pulses of any peptide in its class. Uniquely, Hexarelin also independently stimulates the release of cortisol and prolactin more than any other GHRP and shows cardiovascular cardioprotective properties independent of GH — binding to cardiac CD36 receptors to reduce ischemic damage. This dual GH+cardiac mechanism is the subject of ongoing research.
🎯 Research Use Cases
- ✓Maximum-potency GH stimulation for short-term anabolic cycles
- ✓Cardiovascular protection and post-infarction cardiac repair (independent of GH)
- ✓Evaluation of pituitary GH reserve (diagnostic)
💉 Dosing Protocol
| Typical Dose | 100-200 mcg/injection |
| Frequency | 1-2× daily |
| Half-Life | ~70 minutes |
| Common Vial Sizes | 2 mg, 5 mg |
🧪 Reconstitution Example
⚠️Safety & Considerations
Research peptide. Subject to receptor desensitization — cycle 4 weeks on, 2-4 weeks off. Significantly elevates cortisol and prolactin. Has cardioprotective properties independent of GH.
⚡Interactions & Contraindications
Significant cortisol and prolactin elevation with chronic use. Desensitizes GHS-R1a faster than other GHRPs — limit continuous use to 4 weeks. Contraindicated in prolactin-sensitive conditions (e.g., prolactinoma). Not for use during active cancer treatment.
🔗Synergies & Common Stacks
Produces the highest combined GH release of any GHRH+GHRP combination. Reserve for aggressive short-term protocols due to desensitization risk.
