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ToolsCompareFollistatin vs DS5

Follistatin vs DS5

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

Anabolic & IGF
Follistatin
Sleep Optimization
DS5
Summary
Follistatin is an endogenous glycoprotein that acts as a potent inhibitor of myostatin and activin, two proteins that limit muscle growth. By binding and neutralizing myostatin, follistatin removes the primary brake on skeletal muscle hypertrophy, enabling significant muscle growth beyond normal physiological limits. It is distinct from its isoforms Follistatin 315 and Follistatin 344 in tissue distribution and binding affinity.
DS5 is a synthetic variant of the delta sleep-inducing peptide (DSIP), a nonapeptide originally isolated from rabbit cerebrospinal fluid during slow-wave sleep. Like DSIP, DS5 is explored for sleep optimization, stress modulation, and circadian rhythm normalization, with proposed improvements in potency or stability over the parent molecule.
Half-Life
~3–5 hours (endogenous form)
Estimated 30-60 minutes (peptide degradation)
Admin Route
IM, SubQ
Subcutaneous, Intranasal (research)
Research
Typical Dose
50–100 mcg per injection site
200-500 mcg per dose
Frequency
Every other day or 2–3x per week
Once nightly
Key Benefits
  • Potent myostatin inhibition enabling supraphysiological muscle growth
  • Increases skeletal muscle mass and fiber size
  • May accelerate recovery from muscle injury
  • Potential benefits in muscular dystrophy and sarcopenia
  • Synergistic with IGF-1 and growth hormone in anabolic protocols
  • Animal studies show dramatic increases in muscle mass
  • Reduces muscle fibrosis in dystrophic models
  • Promotes delta-wave (deep) sleep and improves sleep quality
  • May reduce sleep onset latency
  • HPA axis modulation for stress reduction
  • Non-addictive sleep support without tolerance development
  • Potential circadian rhythm normalization
  • Explored for insomnia, chronic stress, and PTSD-related sleep disturbance
Side Effects
  • Potential for excessive muscle growth if doses are not controlled
  • FSH suppression with implications for fertility in women
  • Theoretical risk of cardiac hypertrophy with prolonged high-dose use
  • Limited human safety data available
  • +1 more
  • Generally well-tolerated in research subjects
  • Possible morning grogginess at higher doses
  • Mild blood pressure fluctuations reported with DSIP
  • Limited human safety data for DS5 specifically
Stacks With