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ToolsCompareThymosin Beta-4 vs PT-141 (Bremelanotide)

Thymosin Beta-4 vs PT-141 (Bremelanotide)

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

Recovery & RepairAnti-Aging & Longevity
Thymosin Beta-4
Sexual Health & Libido
PT-141 (Bremelanotide)
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.
PT-141 (Bremelanotide) is a cyclic peptide melanocortin receptor agonist that enhances sexual desire and arousal through central nervous system mechanisms. It is FDA-approved as Vyleesi for premenopausal women with hypoactive sexual desire disorder (HSDD).
Half-Life
Not well characterized; likely similar to TB-500 (~1–2 hours)
2–3 hours
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
5–10 mg
0.5–1.75 mg
Frequency
2x per week (loading), then 1x per week (maintenance)
As needed (not daily)
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
  • Enhances sexual desire and libido in both men and women
  • Improves arousal through central nervous system activation
  • Effective for psychological erectile dysfunction
  • Works for female sexual arousal disorder
  • May improve sexual satisfaction and intensity
  • Fast-acting — effects within 45–60 minutes
  • FDA-approved for HSDD in premenopausal women
Side Effects
  • Generally very well tolerated
  • Injection site reactions
  • Mild fatigue at initiation (repair signaling)
  • Rare: mild inflammatory response
  • +1 more
  • Nausea (most common — 40% of users in clinical trials)
  • Facial flushing and warmth
  • Transient blood pressure changes (typically increase then normalize)
  • Headache
  • +2 more
Stacks With