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ToolsCompareThymalin vs PT-141 (Bremelanotide)

Thymalin vs PT-141 (Bremelanotide)

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

Immune SupportAnti-Aging & Longevity
Thymalin
Sexual Health & Libido
PT-141 (Bremelanotide)
Summary
Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.
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 as a complex extract; individual peptides have varying kinetics
2–3 hours
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
10 mg IM or SC daily
0.5–1.75 mg
Frequency
Once daily
As needed (not daily)
Key Benefits
  • Restores thymic function and T-cell immunity
  • Extends healthy lifespan (documented in long-term studies)
  • Reduces infectious disease incidence in elderly
  • Normalizes immune parameters in immunodeficiency
  • Anti-tumor immune surveillance
  • Improves vaccine response in elderly
  • Reduces cardiovascular mortality (40% in landmark Russian study)
  • Normalizes neuroendocrine function
  • 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
  • Very well tolerated in decades of Russian clinical use
  • Mild injection site reactions
  • Rare: mild allergic reaction (natural extract)
  • Transient flu-like symptoms on initiation (immune activation)
  • 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