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ToolsCompareDSIP vs Follistatin 315

DSIP vs Follistatin 315

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

Sleep OptimizationCognitive Enhancement
DSIP
Anabolic & IGF
Follistatin 315
Summary
DSIP is an endogenous neuropeptide originally isolated from rabbit cerebrospinal fluid that induces delta-wave (deep) sleep. It also modulates stress response, cortisol regulation, and LH secretion, making it valuable for sleep optimization and stress management.
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.
Half-Life
~30–60 minutes; however downstream sleep effects last 4–6 hours
~3–5 hours (longer systemic circulation vs FST-344)
Admin Route
SubQ, IV, Intranasal
SubQ, IM
Research
Typical Dose
100–400 mcg
No established human dosing protocol
Frequency
Once nightly
Research use only
Key Benefits
  • Induces and deepens delta-wave (slow-wave) sleep
  • Reduces cortisol and normalizes HPA axis
  • Improves sleep quality in insomnia patients
  • Anti-stress and anxiolytic effects
  • May improve opiate/alcohol withdrawal symptoms
  • Analgesic properties through opioid modulation
  • Antioxidant and neuroprotective effects
  • 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
Side Effects
  • Generally well tolerated
  • Mild grogginess next morning at higher doses
  • Rare: hypotension
  • Potential for altered dream patterns
  • 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
Stacks With