Hexarelin
Examorelin · HEX · Growth Hormone Secretagogue
The most potent GH secretagogue peptide — delivers dramatic GH spikes but with a catch: rapid desensitisation.
What is Hexarelin?
Hexarelin is a synthetic hexapeptide growth hormone secretagogue — and it is the most potent of its class for acute GH release. A single injection can produce GH spikes rivalling those seen with direct GH injection or insulin tolerance tests. For researchers studying the GH axis, it is a powerful pharmacological tool. For biohackers, it is a double-edged sword.
The catch with Hexarelin is desensitisation. Unlike Sermorelin or Tesamorelin (which work through GHRH receptors and maintain response with chronic use), Hexarelin works through the ghrelin/GHS-R1a receptor — and this receptor downregulates quickly with repeated exposure. After 4-8 weeks of daily use, GH response diminishes significantly. You essentially wear out the receptor.
This makes Hexarelin better suited for short-term, targeted use — burst protocols for injury healing, post-surgery recovery, or as a diagnostic tool — rather than long-term anti-ageing. Some practitioners cycle it (2-4 weeks on, 4 weeks off) to maintain receptor sensitivity, but even this approach may lose efficacy over time.
How Does It Work?
Hexarelin binds the Growth Hormone Secretagogue Receptor (GHS-R1a) — the same receptor that ghrelin activates. This triggers:
1. Direct pituitary GH release — massive acute spike (highest of any GH peptide). 2. Hypothalamic GHRH release — amplifying the pituitary signal. 3. Suppression of somatostatin — removing the brake on GH release. 4. Cardiac protective effects — GHS-R1a is expressed on cardiac tissue; Hexarelin has shown cardioprotective properties independent of GH release.
The triple mechanism (direct pituitary + GHRH increase + somatostatin suppression) explains why GH response is so dramatic. But GHS-R1a desensitisation limits chronic utility.
What Does The Research Say?
Moderate evidence. Some human data, mostly animal studies.
GH release: Extensively studied. Produces 2-3x the GH release of GHRP-6 or GHRP-2 in head-to-head comparisons. Peak GH occurs 15-30 minutes post-injection.
Cardioprotective: Animal and human studies show reduced cardiac fibrosis, improved cardiac function post-MI, and protection against ischaemia-reperfusion injury — independent of GH. This is a unique property among GH secretagogues.
Desensitisation: Well-documented. GH response decreases by 50%+ after 4-8 weeks of daily use. Partial recovery after washout periods.
No FDA approval. Used primarily in research and off-label clinical settings.
Reported Dosages
These are dosages reported in research literature and community reports. They are NOT medical recommendations. Always consult a healthcare professional.
Subcutaneous: 100-200mcg 1-3 times daily (before meals or before bed).
Short cycles recommended: 2-4 weeks maximum, then equal time off.
Some protocols: 200mcg twice daily for injury recovery (2 weeks).
Best on empty stomach (30 min before food).
DISCLAIMER: Research peptide — not approved for human use. Desensitisation is real — do not use chronically. Some users combine with CJC-1295 to maintain response, but this adds complexity and unknowns.
Side Effects & Risks
Acute: intense hunger spike (ghrelin receptor activation), water retention, tingling/numbness (paraesthesia), cortisol and prolactin elevation (more than other GHRPs). Hexarelin raises prolactin and cortisol more than GHRP-2 or Ipamorelin.
Chronic: receptor desensitisation (loss of efficacy), potential prolactin-related issues with extended use (gynaecomastia, libido changes in men). The cortisol/prolactin elevation makes it less 'clean' than Ipamorelin.
Legal Status by Country
Research peptide. Not approved for human use.
Research chemical. Not FDA-approved.
Research peptide. Has been studied clinically in Italy.
Not TGA-approved. Research chemical.
Important Disclaimer
This profile is for educational and research purposes only. It does not constitute medical advice. Hexarelin may be regulated or illegal in your jurisdiction. Do not use any compound without consulting a qualified healthcare professional. StackPedia does not sell, supply, or promote the use of any controlled substance.