Hexarelin
Research OnlyThe most potent synthetic GHRP (Growth Hormone Releasing Peptide), a hexapeptide that strongly stimulates GH release via the ghrelin receptor. Notable for cardioprotective effects independent of GH release. Development discontinued due to rapid desensitization with repeated dosing. Italian research leads global investigation.
Examorelin · HEX · Growth Hormone Releasing Hexapeptide · MF-6003 · EP-23905
18 human studies
- Preclinical
- 36%
- Human research
- 43%
Based on 42 cited sources
Numeric assessment unreviewed
A historical numeric score is recorded but has not passed a current, compound-specific assessment review. No numeric score is displayed.
This is a limitation of the numeric assessment, not a measured absence of benefit. It does not re-review the separately recorded catalogue classification or establish efficacy or safety.
Hexarelin is the most potent synthetic growth hormone secretagogue, acting primarily through the ghrelin receptor (GHS-R1a). Unique among GHRPs, it also exhibits GH-independent cardioprotective effects via CD36 receptor binding.
How It Works (Simplified)
Hexarelin triggers powerful GH release but with a critical limitation - rapid desensitization:
Binds GHS-R1a on pituitary somatotrophs, triggering calcium release and potent GH secretion - in human studies roughly 2x the response to GHRH.
Uniquely binds CD36 on cardiomyocytes, activating PPAR-gamma and anti-apoptotic pathways independent of GH release.
High receptor affinity causes rapid receptor internalization - the GH response to repeated dosing is blunted, with no sustained IGF-1 elevation.
Minimal cortisol/prolactin elevation compared to GHRP-6/GHRP-2, though less selective than ipamorelin.
Key Research: Ghigo E et al. (Turin, 1994) characterized hexarelin’s GH-releasing activity across routes in human studies, showing a GH response about 2x greater than GHRH. PMID:8126144
Important Limitations
- Rapid desensitization (4-7 days) ended pharmaceutical development
- Cardioprotective effects primarily demonstrated in animal models
- No sustained IGF-1 elevation achievable with chronic dosing
- Long-term safety data limited due to desensitization preventing chronic exposure
- Not approved by any regulatory agency for therapeutic use
Research Tools
- Hexarelin Reconstitution Calculator — calculate concentration from vial mass and diluent volume (educational tool only)
Reported positives
- Strong GH release reported comparable to GHRP-6
- Cardioprotective properties noted in research
- Improved recovery and sleep quality reported
- Potent effects from relatively small amounts
Reported negatives
- Rapid desensitization with continued use
- Cortisol and prolactin elevation concerns
- Hunger increase though less than GHRP-6
- Limited long-term safety data
“Known as the most potent GHRP. Community notes rapid desensitization as major drawback.”
Self-reported, unverified accounts — not clinical evidence and no substitute for the cited research. Anecdotes are prone to selection bias and placebo effects.
Based on human studies: GH peak occurs 15-30 minutes after subcutaneous or IV administration. GH response is approximately 2x greater than GHRH. Single-dose effects are potent and reliable.
PMID:8126144Initial doses maintain strong GH response. Subcutaneous administration achieves a GH response comparable to the IV route. Cardioprotective effects may occur with each dose independent of GH status.
PMID:8126144Desensitization develops with repeated dosing. The GH response to a subsequent dose is blunted and no rise in IGF-1 is achieved. This tolerance limited pharmaceutical development.
PMID:11888836Continued dosing produces a desensitized GH response. Recovery of sensitivity requires a washout period. This desensitization profile makes hexarelin unsuitable for chronic therapy.
PMID:9186261Research-based observations
This timeline reflects observations from published clinical and preclinical studies. Individual responses may vary significantly. This is not a guarantee of effects or a dosing schedule. Consult qualified healthcare providers for personalized guidance.
Sermorelin
SynergisticClassic GHRH+GHRP synergy. Sermorelin (GHRH) and hexarelin (GHRP) produce greater GH release than either alone.
BPC-157
CompatibleDifferent mechanisms - hexarelin for GH release, BPC-157 for tissue repair. No known interactions.
GHRP-6
AvoidBoth are GHRPs acting on the same receptor (GHS-R1a). Combining provides no additional benefit and hexarelin desensitizes faster than GHRP-6.
GHRP-2
AvoidBoth are GHRPs targeting GHS-R1a. No benefit to combining as they share mechanism. Use one or the other.
Ipamorelin
AvoidBoth GHRPs acting on same receptor. Ipamorelin is more selective with less desensitization; combining offers no advantage.
Research Note: Interaction data is based on published literature, mechanistic understanding, and theoretical considerations. Most peptide combinations lack direct clinical study. This information is for educational purposes only and does not constitute medical advice. Always consult qualified healthcare providers.
Key Studies Cited
Use the source links in the research discussion above to inspect the referenced records.
This dossier synthesizes available evidence from peer-reviewed literature, regulatory documents, and clinical trial registries. Evidence strength labels summarize the cited material for this entry and should be read alongside its population, model, and study limitations.
For complete methodology details, see our Methodology page.
Important Disclaimer
This dossier is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making health decisions.
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Compare Hexarelin
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Compared With
3 comparisonsConditions Studied
3 entries- Hexarelin for Growth Hormone Stimulation Hexarelin is among the most potent synthetic GHRPs for acute GH release. Human studies showed GH responses approximately 2x greate…
- Hexarelin for Cardioprotection Hexarelin exhibits cardioprotective effects via myocardial GH secretagogue receptor binding, independent of GH release. Animal stu…
- Hexarelin for Sleep Effects Repeated nocturnal hexarelin decreased slow-wave sleep in a human study, with concurrent rises in GH, ACTH, cortisol and prolactin…