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ToolsCompareThymosin Beta-4 vs Leuprolide

Thymosin Beta-4 vs Leuprolide

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

Recovery & RepairAnti-Aging & Longevity
Thymosin Beta-4
Sexual Health & Libido
Leuprolide
Summary
Thymosin Beta-4 is an endogenous 43-amino acid peptide that is the primary intracellular actin sequestering peptide. It promotes tissue repair, reduces inflammation, regenerates hair follicles, and protects cardiac tissue. Closely related to TB-500 (the active fragment), it is used for systemic tissue recovery and anti-aging.
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
Not well characterized; likely similar to TB-500 (~1–2 hours)
~3 hours (SC/IM), but depot formulations last 1–12 months
Admin Route
SubQ, IM
SubQ, IM
Research
Typical Dose
5–10 mg
7.5 mg monthly, 22.5 mg 3-monthly, or 45 mg 6-monthly
Frequency
2x per week (loading), then 1x per week (maintenance)
Per depot schedule
Key Benefits
  • Systemic tissue repair and regeneration
  • Promotes cardiac recovery after myocardial infarction
  • Hair follicle regeneration and anti-hair-loss
  • Anti-inflammatory (systemic)
  • Wound healing acceleration
  • Neuroprotection after brain injury
  • Protects against ischemia-reperfusion injury
  • Anti-aging at cellular level
  • Synergizes powerfully with BPC-157
  • 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
  • Generally very well tolerated
  • Injection site reactions
  • Mild fatigue at initiation (repair signaling)
  • Rare: mild inflammatory response
  • +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