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ToolsCompareFollistatin 344 vs Thymulin

Follistatin 344 vs Thymulin

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

Anabolic & IGF
Follistatin 344
Immune Support
Thymulin
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.
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Half-Life
~24–36 hours
~30 minutes active half-life
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
100 mcg
20-30 mcg
Frequency
Once daily
10 days per month (Khavinson protocol)
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
  • Enhances T-cell maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
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)
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With