New — Free Peptide Starter Guide (2026): 13 chapters, 34 cited studies

Get it free
ToolsCompareFollistatin 344 vs Thymagen

Follistatin 344 vs Thymagen

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

Anabolic & IGF
Follistatin 344
Immune Support
Thymagen
Summary
Follistatin 344 is a recombinant form of the endogenous follistatin protein. It inhibits myostatin and activin — the primary negative regulators of muscle growth — potentially removing the genetic ceiling on muscle development. It is one of the most theoretically powerful anabolic compounds but is experimental with limited human data.
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
~24–36 hours
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ, IM
SubQ, Oral
Research
Typical Dose
100 mcg
10 mg per day
Frequency
Once daily
Daily for 10–30 days
Key Benefits
  • Inhibits myostatin — removes muscle growth ceiling
  • Significant increases in muscle mass and strength
  • Reduces fat mass
  • Promotes bone density
  • May stimulate hair follicle cycling
  • Anti-fibrotic effects in muscle tissue
  • Synergistic with IGF-1 and other anabolic peptides
  • 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
  • Muscle soreness (from rapid hypertrophy)
  • Potential reproductive effects (activin inhibition)
  • Unknown long-term safety profile
  • Possible esophageal effects at high doses (animal data)
  • Generally well tolerated
  • Mild injection site reactions
  • No significant immunological adverse events reported
Stacks With