Hexarelin
Also known as: Examorelin · L-692,585 · growth hormone releasing peptide-6 analogue
A synthetic hexapeptide growth-hormone-releasing peptide with the most potent GH-releasing activity in the class, and distinctive cardioprotective effects mediated by a non-GH-mediated mechanism.
Hexarelin is the most potent GHRP-family compound with distinctive cardioprotective effects via cardiac CD36 receptor engagement independent of the GH-axis mechanism.
Evidence tier: C — preclinical / mechanistic evidence only
- Category
- Sleep & Recovery
- Half-life
- Approximately 55 minutes plasma
Section 1
Overview
Hexarelin (examorelin) is a synthetic hexapeptide growth-hormone-releasing peptide developed by the Ghigo laboratory in Italy as one of the more potent GHRP-family compounds. Its distinctive research profile is characterised by two features: substantially higher GH-releasing potency than the earlier GHRPs (GHRP-2, GHRP-6), and independent cardioprotective effects mediated through a non-GH-mediated mechanism involving cardiac CD36 receptor engagement.
In research-peptide practice, Hexarelin is used both as a GH-axis research tool (typically in combination with GHRH analogues) and as a research tool for the cardioprotective mechanism. The cardioprotective research angle extends the compound's research applications beyond the primary GH-axis endocrine-and-cognitive-relevance research into cardiovascular research contexts.
Cognitive-relevance research applications follow the same GH-axis framework as the other GHRP-family compounds — sleep-onset GH pulse augmentation with indirect cognitive-relevance via sleep-mediated memory consolidation. The compound's higher GH-releasing potency provides a research-tool advantage for research applications requiring strong GH-axis stimulation.
Section 2
Discovery & History
- Developed by the Ghigo laboratory in Italy in the 1990s as a next-generation GHRP with substantially higher GH-releasing potency than GHRP-2 and GHRP-6.
- Underwent extensive academic research characterisation across the 1990s and 2000s for both GH-axis pharmacology and the independent cardioprotective mechanism.
- Cardioprotective effects mediated through cardiac CD36 receptor engagement were characterised as a distinctive mechanism separate from the primary GH-releasing pharmacology.
- Did not progress to marketing authorisation despite substantial mechanistic characterisation.
- Continues to be used in research-peptide practice as a potent GH-axis research tool and in cardiovascular research contexts.
Section 3
Mechanism of Action
- 1Ghrelin-receptor (GHSR-1a) agonism on pituitary somatotroph cells, driving GH release from the pituitary with substantially higher potency than earlier GHRPs.
- 2Reduced but not absent off-target effects on cortisol, prolactin, and ACTH release relative to the earlier GHRPs — intermediate between the highly-selective Ipamorelin and the earlier less-selective GHRP-2 and GHRP-6.
- 3Independent cardioprotective mechanism via cardiac CD36 receptor engagement — a distinctive non-GH-mediated pathway that operates through the cardiac scavenger-receptor system rather than the primary GH-axis pathway.
- 4Combined pulse-effect with GHRH analogues — Hexarelin provides potent ghrelin-receptor arm signalling that potentiates the GHRH-receptor arm signalling from CJC-1295 or Sermorelin.
- 5Systemic GH-mediated effects — increased IGF-1 production, downstream metabolic and tissue-repair effects, and CNS-relevant IGF-1 signalling.
- 6Sleep-onset GH pulse augmentation providing the indirect cognitive-relevance mechanism via sleep-mediated memory consolidation.
- 7Reported effects on body composition (lean mass, adiposity) via the systemic GH mechanism.
Section 4
Researched Benefits
Findings reported in the published preclinical and clinical literature. Effects in research contexts do not constitute claims of therapeutic benefit in humans.
- 1Highest GH-releasing potency in the GHRP class — appropriate for research applications requiring strong GH-axis stimulation.
- 2Distinctive cardioprotective mechanism via cardiac CD36 receptor engagement — a research-tool niche unshared by other GHRPs.
- 3Effective research-tool combination with GHRH analogues for physiological GH-pulse research.
- 4Reported effects on body composition, tissue-repair markers, and metabolic parameters in research applications.
- 5Sleep-onset GH pulse augmentation with indirect cognitive-relevance via sleep-mediated memory consolidation.
- 6Substantial academic research characterisation across GH-axis and cardiovascular research contexts.
- 7Distinctive research applications extending beyond the primary GH-axis endocrine research into cardiovascular research.
Section 5
Theoretical Dosing & Protocols
| Route | Dosage | Frequency | Duration |
|---|---|---|---|
| Subcutaneous injection (research) | 100-200 mcg per dose in most research protocols | 1-3× daily in the standard research configuration | Research protocol dependent; chronic research use continues 4-8 weeks in most contexts, shorter than for the less-potent GHRPs |
Note: Chronic use typically limited by tolerance-development to the GH-releasing effect (unlike the more selective Ipamorelin).
Section 6
Administration Routes
- Subcutaneous injection — the primary research route.
- Intramuscular administration in some research contexts.
- Oral administration is not viable.
- Intranasal administration explored in some research applications but not the standard route.
Section 7
Safety Profile
Commonly reported
- · Injection-site reactions with subcutaneous administration.
- · Occasional headache during initial dosing.
- · Mild transient effects on cortisol, prolactin, and ACTH (more pronounced than for Ipamorelin) — the reduced-but-not-absent off-target effect.
- · Fluid retention and mild peripheral oedema — expected GH-mediated effect.
- · Occasional mild fatigue or drowsiness reported after dosing.
Rare / theoretical
- · Tolerance development to the GH-releasing effect with chronic use — the reason chronic protocols are typically shorter than for Ipamorelin.
- · Diabetes precipitation or worsening of glycaemic control in susceptible research subjects.
- · GH-mediated effects on cardiac hypertrophy in chronic high-dose research.
- · Theoretical GH-mediated tumour-growth concerns in active malignancy.
- · Rare hypersensitivity reactions.
Contraindications
- · Not authorised for human use in the UK.
- · Active malignancy — theoretical contraindication via the GH-axis mechanism.
- · Pregnancy and lactation.
- · Severe uncontrolled diabetes.
Section 8
UK & EU Regulatory Context
United Kingdom
Not a licensed medicine in the UK. Research chemical only.
European Union
Not approved by the EMA.
Section 9
Clinical Studies Summary
Hexarelin GH-releasing potency characterisation
Clinical pharmacology characterisation of Hexarelin's GH-releasing potency demonstrating substantially higher activity than GHRP-2 and GHRP-6 at equivalent doses. Established the compound's positioning as the most potent GHRP-family research tool.
Hexarelin cardioprotective mechanism — CD36 receptor engagement
Molecular pharmacology characterisation of Hexarelin's cardioprotective mechanism via cardiac CD36 receptor engagement, demonstrating the distinctive non-GH-mediated pathway that operates through the cardiac scavenger-receptor system rather than the primary GH-axis pathway. Established the compound's distinctive cardiovascular research application niche.
Hexarelin in aged-population GH-axis research
Clinical research applications of Hexarelin in age-related GH decline populations, reporting GH-axis restoration and modest secondary effects on body composition and metabolic parameters. Extends the GH-axis research applications into aged-population contexts.
Hexarelin cardioprotection in ischaemia-reperfusion models
Preclinical cardiovascular research characterising Hexarelin's cardioprotective effects in ischaemia-reperfusion injury models, reporting reduced infarct volume and preserved cardiac function in treated cohorts via the CD36-mediated mechanism.
Section 10
Frequently Asked Questions
Section 10a
Practical Research Guidance
Cycle guidance
Reconstitution & storage
UK sourcing notes
Section 11
Sourcing for Laboratory Research
Sourcing Hexarelin for laboratory research
Researchers in the United Kingdom and elsewhere typically obtain Hexarelin from specialist research-chemical suppliers. Purity, third-party testing, and supplier transparency are the principal differentiators worth evaluating before placing an order. The two suppliers below are commonly referenced in UK research contexts.
Reminder: research peptides are sold strictly for in vitro and preclinical laboratory purposes. Importation or supply for human consumption is not permitted under UK medicines legislation.