Hexarelin vs SS-31 (Elamipretide)

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

HexarelinSS-31 (Elamipretide)
CategoryPeptidesPeptides
Standard DoseResearch indicates 100-200 mcg administered 1-2 times daily via subcutaneous injection.Research indicates 0.05-0.25 mg/kg daily via subcutaneous injection. Clinical trials used 4-40 mg/day IV or SC.
TimingOn empty stomach, bedtime preferred. Avoid prolonged continuous use due to rapid desensitization.Morning dosing preferred. No food timing restrictions.
Cycle Duration4-8 week cycles maximum, then 4+ week break. Hexarelin desensitizes faster than other GHRPs.Clinical trials ranged from single dose to 48 weeks. Optimal cycle length not established.
Evidence Levelmoderate_humanEmerging (Phase 2/3 trials)
A

Hexarelin

Peptides

Mechanism

Hexarelin (Examorelin) is a synthetic hexapeptide GHS-R1a agonist and the most potent synthetic GH secretagogue by peak GH release. It stimulates GH release through both pituitary ghrelin receptors and hypothalamic pathways, with mechanisms involving regulation of GHRH and somatostatin. Hexarelin also demonstrates significant cardiac benefits through activation of cardiac GHS-R1a receptors, protecting against ischemia-reperfusion injury and reducing cardiac fibrosis via the CD36 scavenger receptor pathway.

Standard Dosing

Research indicates 100-200 mcg administered 1-2 times daily via subcutaneous injection.

Timing

On empty stomach, bedtime preferred. Avoid prolonged continuous use due to rapid desensitization.

Cycle Duration

4-8 week cycles maximum, then 4+ week break. Hexarelin desensitizes faster than other GHRPs.

Side Effects

  • Significant cortisol elevation
  • Prolactin increase
  • Water retention
  • Joint pain
  • Rapid desensitization (unique to Hexarelin)

Contraindications

  • Active cancer
  • Cardiac arrhythmias (due to direct cardiac receptor activity)
  • Cushing's syndrome
  • Pregnancy and breastfeeding

Best Stacking Partners

CJC-1295 (no DAC)Sermorelin

Mechanism

SS-31 (D-Arg-Dmt-Lys-Phe-NH2, also known as elamipretide/Bendavia) is a cell-permeable tetrapeptide that localizes to the inner mitochondrial membrane and binds cardiolipin via electrostatic interactions. This stabilizes cardiolipin against oxidative damage, preserving cristae integrity, reducing ROS production, and maintaining mitochondrial ATP production. SS-31 interacts with proteins in two functional groups: oxidative phosphorylation complexes and 2-oxoglutarate metabolic enzymes — all known cardiolipin binders. It restores mitochondrial function without acting as a direct antioxidant.

Standard Dosing

Research indicates 0.05-0.25 mg/kg daily via subcutaneous injection. Clinical trials used 4-40 mg/day IV or SC.

Timing

Morning dosing preferred. No food timing restrictions.

Cycle Duration

Clinical trials ranged from single dose to 48 weeks. Optimal cycle length not established.

Side Effects

  • Injection site reactions
  • Headache
  • Diarrhea (in clinical trials)
  • Nausea

Contraindications

  • Pregnancy and breastfeeding
  • Severe renal impairment (peptide clearance concern)
  • Not commercially available
  • Clinical trial participants only

Best Stacking Partners

MOTS-cHumaninEpitalon

Not sure which is right for you?

Take our free assessment to get personalized recommendations based on your health goals, current stack, and biomarkers.

Get Your Free Protocol →or take the assessment →