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ToolsCompareFollistatin vs Sermorelin

Follistatin vs Sermorelin

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

Anabolic & IGF
Follistatin
Growth Hormone PeptidesAnti-Aging & Longevity
Sermorelin
Summary
Follistatin is an endogenous glycoprotein that acts as a potent inhibitor of myostatin and activin, two proteins that limit muscle growth. By binding and neutralizing myostatin, follistatin removes the primary brake on skeletal muscle hypertrophy, enabling significant muscle growth beyond normal physiological limits. It is distinct from its isoforms Follistatin 315 and Follistatin 344 in tissue distribution and binding affinity.
Sermorelin is a bioidentical synthetic peptide comprising the first 29 amino acids of naturally occurring GHRH. It is FDA-approved for diagnostic use and widely prescribed off-label for anti-aging, stimulating growth hormone production in a natural pulsatile pattern that mimics the body's own rhythm.
Half-Life
~3–5 hours (endogenous form)
10–20 minutes
Admin Route
IM, SubQ
SubQ
Research
Typical Dose
50–100 mcg per injection site
200–500 mcg
Frequency
Every other day or 2–3x per week
5–7 days per week
Key Benefits
  • Potent myostatin inhibition enabling supraphysiological muscle growth
  • Increases skeletal muscle mass and fiber size
  • May accelerate recovery from muscle injury
  • Potential benefits in muscular dystrophy and sarcopenia
  • Synergistic with IGF-1 and growth hormone in anabolic protocols
  • Animal studies show dramatic increases in muscle mass
  • Reduces muscle fibrosis in dystrophic models
  • Increases energy and vitality
  • Improves body composition (more muscle, less fat)
  • Enhances skin thickness and elasticity
  • Strengthens immune system
  • Improves sleep quality and REM sleep
  • Supports bone density
  • Enhances mental clarity and focus
  • Safer than exogenous HGH — respects natural feedback loops
  • FDA-approved for GH diagnostic use
Side Effects
  • Potential for excessive muscle growth if doses are not controlled
  • FSH suppression with implications for fertility in women
  • Theoretical risk of cardiac hypertrophy with prolonged high-dose use
  • Limited human safety data available
  • +1 more
  • Injection site irritation
  • Flushing
  • Headache
  • Dizziness
  • +2 more
Stacks With