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ToolsCompareSS-31 (Elamipretide) vs MK-677 (Ibutamoren)

SS-31 (Elamipretide) vs MK-677 (Ibutamoren)

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

Anti-Aging & Longevity
SS-31 (Elamipretide)
Growth Hormone Peptides
MK-677 (Ibutamoren)
Summary
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.
MK-677 (Ibutamoren) is an orally active, non-peptide ghrelin receptor agonist that increases growth hormone and IGF-1 levels. Unlike injectable GHRPs, it can be taken orally and has a 24-hour half-life, making it convenient for sustained GH optimization.
Half-Life
~2–5 hours
24 hours
Admin Route
SubQ
Oral
Research
Typical Dose
5–10 mg
10–25 mg
Frequency
Daily to several times per week
Once daily
Key Benefits
  • 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
  • Increases lean muscle mass
  • Enhances bone density
  • Improves sleep quality and REM sleep
  • Accelerates recovery from training
  • Increases appetite
  • May improve skin elasticity and appearance
  • Supports fat loss while maintaining muscle
  • Oral administration — no injections required
  • 24-hour half-life allows once-daily dosing
Side Effects
  • Injection site irritation
  • Nausea (rare)
  • Generally well-tolerated in clinical trials
  • Increased appetite (significant in some users)
  • Water retention and puffiness
  • Elevated blood glucose / insulin resistance (monitor in diabetics)
  • Lethargy initially
  • +2 more
Stacks With