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ToolsCompareFollistatin 344 vs P21

Follistatin 344 vs P21

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

Anabolic & IGF
Follistatin 344
Cognitive EnhancementAnti-Aging & Longevity
P21
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.
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Half-Life
~24–36 hours
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ, IM
SubQ, Intranasal
Research
Typical Dose
100 mcg
100–500 mcg
Frequency
Once daily
Once daily
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
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
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 in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With