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ToolsCompareSomatropin (HGH) vs SS-31 (Elamipretide)

Somatropin (HGH) vs SS-31 (Elamipretide)

Side-by-side comparison of key properties, dosing, and research.

Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)
Anti-Aging & Longevity
SS-31 (Elamipretide)
Summary
Somatropin is recombinant human growth hormone (rhGH), identical in structure to the 191-amino acid pituitary-derived growth hormone. It is FDA-approved for growth hormone deficiency, short stature, and wasting conditions. Off-label, it is widely explored for body composition, anti-aging, and performance enhancement, though significant risks accompany unsupervised use.
SS-31 (Elamipretide) is a synthetic mitochondria-targeting tetrapeptide that concentrates in the inner mitochondrial membrane and protects cardiolipin from oxidative damage. It is one of the most promising mitochondrial longevity compounds, studied in clinical trials for heart failure, renal disease, and age-associated mitochondrial dysfunction.
Half-Life
2-3 hours (subcutaneous); 20-30 minutes (intravenous)
~2–5 hours
Admin Route
Subcutaneous, Intramuscular (less common)
SubQ
Research
Typical Dose
0.15-0.3 mg/day (adults); titrated to IGF-1 levels
5–10 mg
Frequency
Once daily
Daily to several times per week
Key Benefits
  • Increases lean muscle mass and reduces body fat (particularly visceral)
  • Restores growth hormone deficiency (FDA-approved)
  • Improves bone mineral density
  • Enhances exercise capacity and recovery
  • Supports skin thickness and collagen synthesis
  • Improves lipid profile in GHD patients
  • Explored for anti-aging and cellular regeneration
  • Restores mitochondrial function and ATP production
  • Protects inner mitochondrial membrane cardiolipin
  • Reduces mitochondrial reactive oxygen species (ROS)
  • Improves exercise capacity and reduces fatigue
  • Cardioprotective — studied in heart failure trials
  • Renoprotective — reduces ischemic kidney injury
  • Anti-aging via mitochondrial preservation
  • Potential in neurodegenerative disease prevention
Side Effects
  • Fluid retention and edema (common, dose-dependent)
  • Carpal tunnel syndrome
  • Joint and muscle pain
  • Insulin resistance and elevated blood glucose
  • +3 more
  • Injection site irritation
  • Nausea (rare)
  • Generally well-tolerated in clinical trials
Stacks With