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ToolsCompareSelank vs Thymalin

Selank vs Thymalin

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

Cognitive Enhancement
Selank
Immune SupportAnti-Aging & Longevity
Thymalin
Summary
Selank is a synthetic heptapeptide analog of tuftsin developed in Russia. It is a potent anxiolytic that reduces anxiety and enhances cognitive function without sedation or addiction. It is approved for clinical use in Russia for anxiety disorders.
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.
Half-Life
Minutes (but effects persist for hours)
Not well characterized as a complex extract; individual peptides have varying kinetics
Admin Route
SubQ, Intranasal
SubQ, IM
Research
Typical Dose
250–500 mcg
10 mg IM or SC daily
Frequency
1–3 times daily
Once daily
Key Benefits
  • Reduces anxiety without sedation
  • Enhances memory and learning
  • Improves focus and concentration
  • Stabilizes mood
  • Reduces physiological stress response
  • May enhance motivation
  • No addiction potential or withdrawal
  • Fast-acting — effects within 20–30 minutes
  • Approved clinically in Russia for anxiety disorders
  • 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
Side Effects
  • Mild sedation at higher doses (paradoxical)
  • Fatigue (rare)
  • Irritability during discontinuation (uncommon)
  • 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)
Stacks With