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ToolsCompareFollistatin vs Thymagen

Follistatin vs Thymagen

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

Anabolic & IGF
Follistatin
Immune Support
Thymagen
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.
Thymagen is a dipeptide bioregulator (Glu-Asp) developed by Professor Vladimir Khavinson, tissue-specific for the thymus gland. It supports T-lymphocyte maturation, thymic function, and immune system normalization. As the thymus involutes with age (thymic atrophy), immune competence declines. Thymagen is used to support immune restoration, particularly in aging, post-illness recovery, and immunodeficiency states.
Half-Life
~3–5 hours (endogenous form)
Short (minutes); sustained gene-regulatory effects
Admin Route
IM, SubQ
SubQ, Oral
Research
Typical Dose
50–100 mcg per injection site
10 mg per day
Frequency
Every other day or 2–3x per week
Daily for 10–30 days
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
  • Supports thymic epithelial cell function and T-cell maturation
  • May partially restore thymic output reduced by age-related atrophy
  • Normalizes T-lymphocyte subpopulation balance
  • Supports immune recovery after illness, surgery, or chemotherapy
  • Anti-aging effects on thymic tissue
  • Complementary to Thymosin Alpha-1 and Thymalin in immune protocols
  • May improve vaccine responsiveness in older individuals
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
  • Generally well tolerated
  • Mild injection site reactions
  • No significant immunological adverse events reported
Stacks With