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ToolsCompareFollistatin vs Selank

Follistatin vs Selank

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

Anabolic & IGF
Follistatin
Cognitive Enhancement
Selank
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.
Selank is a synthetic heptapeptide analog of tuftsin developed in Russia. It is a potent anxiolytic that reduces anxiety and enhances cognitive function without sedation or addiction. It is approved for clinical use in Russia for anxiety disorders.
Half-Life
~3–5 hours (endogenous form)
Minutes (but effects persist for hours)
Admin Route
IM, SubQ
SubQ, Intranasal
Research
Typical Dose
50–100 mcg per injection site
250–500 mcg
Frequency
Every other day or 2–3x per week
1–3 times daily
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
  • Reduces anxiety without sedation
  • Enhances memory and learning
  • Improves focus and concentration
  • Stabilizes mood
  • Reduces physiological stress response
  • May enhance motivation
  • No addiction potential or withdrawal
  • Fast-acting — effects within 20–30 minutes
  • Approved clinically in Russia for anxiety disorders
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
  • Mild sedation at higher doses (paradoxical)
  • Fatigue (rare)
  • Irritability during discontinuation (uncommon)
Stacks With