Hexarelin for Growth Hormone Stimulation & Cardioprotection — Performance & Recovery

Most potent GH secretagogue with cardiovascular benefits. Phase I/II human trials. Significant desensitization. NOT FDA-approved.

Overview

Hexarelin (Examorelin, EP-23905) is a synthetic hexapeptide growth hormone secretagogue (GHS) that potently stimulates GH release via the ghrelin receptor (GHS-R1a). It is the MOST POTENT GH secretagogue studied in humans, with ED50 of 0.50 mcg/kg IV. CLINICAL DATA: Well-characterized dose-response in healthy adults (Imbimbo 1994): peak GH of 26.9-55.0 ng/mL depending on dose. Pediatric intranasal study showed 36% IGF-1 increase and growth velocity improvement from 5.3 to 8.3 cm/year over 8 months. CRITICAL LIMITATIONS: 1) Significant DESENSITIZATION occurs — GH response decreases 36% by week 4 and 45% by week 16 of continuous use (fully reversible with 4-week washout). 2) Unlike Ipamorelin, Hexarelin INCREASES cortisol AND prolactin levels, making it a less clean secretagogue. 3) Chronic therapy did NOT significantly raise IGF-1 in adults despite acute GH elevation. UNIQUE ADVANTAGE: CD36 receptor-mediated cardioprotective effects — decreased atherosclerotic lesions and improved cardiac contractility in preclinical models. NOT FDA-approved. Available as research peptide.

Indications

  • Growth hormone stimulation (most potent GHS - ED50 0.50 mcg/kg IV)
  • Pediatric growth support (IGF-1 +36%, growth velocity 5.3→8.3 cm/yr in 8-month trial)
  • Cardiovascular protection (CD36-mediated, decreased atherosclerotic lesions)
  • Fat oxidation and visceral fat reduction
  • Lean mass support and muscle preservation
  • Lipid profile improvement (decreased triglycerides, decreased liver fat in insulin-resistant models)
  • Improved glucose tolerance (preclinical insulin-resistant models)
  • Sleep improvement (increased Stage 4/REM sleep - similar to other GHS)

Mechanism of Action

Declining GH secretion with aging leads to reduced muscle mass, increased body fat, impaired recovery, cardiovascular changes, and metabolic dysfunction

Dosing

CompoundDoseFrequencyNotes
Hexarelin100-200 mcg2-3 times daily for 4-8 weeksStandard research dose. Fasted state required. Most potent at 1-2 mcg/kg.
Hexarelin60 mcg/kg3 times dailyPediatric intranasal dose from 8-month growth study. IGF-1 increased 36%.

Evidence Grade

GRADE C

Safety & Contraindications

  • CRITICAL: NOT FDA-approved for any indication
  • SIGNIFICANT DESENSITIZATION: GH response decreases 36% by week 4, 45% by week 16 (fully reversible with 4-week washout)
  • INCREASES cortisol AND prolactin (unlike Ipamorelin which does not)
  • Chronic therapy did NOT significantly raise IGF-1 in adults
  • Well-tolerated in acute dosing (0.5-2 mcg/kg IV) - no significant glucose, TSH, FSH, LH changes
  • BANNED by WADA and most athletic organizations
  • Fasted state required for optimal GH pulse (1 hr before or 3 hrs after food)
  • No long-term body composition or bone density changes observed in 16-week adult study
  • Available only as research peptide
  • Cycling REQUIRED: 12-16 weeks ON, 4-6 weeks OFF minimum