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ToolsCompareFollistatin vs Leuprolide

Follistatin vs Leuprolide

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

Anabolic & IGF
Follistatin
Sexual Health & Libido
Leuprolide
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.
Leuprolide is a synthetic GnRH superagonist that, with continuous administration, paradoxically suppresses LH and FSH through receptor desensitization — the opposite effect of pulsatile GnRH. Used medically for prostate cancer, endometriosis, and precocious puberty. In men's health, short-duration use for PCT and testosterone suppression rebound.
Half-Life
~3–5 hours (endogenous form)
~3 hours (SC/IM), but depot formulations last 1–12 months
Admin Route
IM, SubQ
SubQ, IM
Research
Typical Dose
50–100 mcg per injection site
7.5 mg monthly, 22.5 mg 3-monthly, or 45 mg 6-monthly
Frequency
Every other day or 2–3x per week
Per depot schedule
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
  • Medical: reduces testosterone in prostate cancer
  • Medical: suppresses estrogen in endometriosis and uterine fibroids
  • Medical: delays precocious puberty
  • Research: testosterone rebound effect after short course
  • Transgender care: hormone suppression in adolescents
  • Research: hormonal re-sensitization protocols
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
  • Hot flashes (with testosterone suppression)
  • Decreased libido and erectile dysfunction
  • Initial testosterone flare (first 1–2 weeks)
  • Bone density loss with long-term use
  • +3 more
Stacks With