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ToolsCompareFollistatin 315 vs BPC-157

Follistatin 315 vs BPC-157

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

Anabolic & IGF
Follistatin 315
Recovery & Repair
BPC-157
Summary
Follistatin 315 is a splice variant isoform of follistatin produced by alternative mRNA processing. Unlike Follistatin 344 which is tethered to cell surfaces via heparan sulfate proteoglycans, FST-315 circulates freely in the bloodstream and has broader systemic distribution. It is the predominant circulating form and exerts systemic myostatin inhibition as well as FSH suppression, making it relevant to both muscle growth and reproductive endocrinology.
BPC-157 is a synthetic pentadecapeptide derived from a protective protein found in the stomach. It is one of the most extensively researched healing peptides, known for accelerating tissue repair, reducing inflammation, and protecting the gastrointestinal tract.
Half-Life
~3–5 hours (longer systemic circulation vs FST-344)
4–6 hours
Admin Route
SubQ, IM
SubQ, IM, Oral
Research
Typical Dose
No established human dosing protocol
200–500 mcg
Frequency
Research use only
Once daily
Key Benefits
  • Systemic myostatin inhibition for whole-body muscle growth
  • Freely circulating — broader tissue distribution than FST-344
  • Strong FSH-suppressive activity useful in certain hormonal protocols
  • Potential for greater anabolic effect across multiple muscle groups simultaneously
  • May be more relevant to reproductive endocrinology applications
  • Studied in gene therapy approaches for muscular dystrophy
  • Accelerates wound healing and tissue repair
  • Reduces inflammation throughout the body
  • Protects and heals the gastrointestinal tract
  • Supports tendon and ligament healing
  • Promotes bone and joint health
  • May protect organs from toxins and injury
  • Supports gut-brain axis function
  • Counteracts NSAID-induced gut damage
Side Effects
  • Systemic FSH suppression — significant concern for fertility
  • Greater potential for off-target effects vs FST-344 due to systemic distribution
  • Limited human safety data
  • Potential cardiac hypertrophy with prolonged high-dose exposure
  • Injection site discomfort
  • Nausea (rare)
  • Headache (rare)
  • Dizziness (rare)
Stacks With