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ToolsCompareLeuprolide vs Thymulin

Leuprolide vs Thymulin

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

Sexual Health & Libido
Leuprolide
Immune Support
Thymulin
Summary
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.
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Half-Life
~3 hours (SC/IM), but depot formulations last 1–12 months
~30 minutes active half-life
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
7.5 mg monthly, 22.5 mg 3-monthly, or 45 mg 6-monthly
20-30 mcg
Frequency
Per depot schedule
10 days per month (Khavinson protocol)
Key Benefits
  • 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
  • Enhances T-cell maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
Side Effects
  • 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
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With