Thymulin vs Selank
Side-by-side comparison of key properties, dosing, and research.
- Summary
- 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.
- 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.
- Half-Life
- ~30 minutes active half-life
- Minutes (but effects persist for hours)
- Admin Route
- SubQ
- SubQ, Intranasal
- Research
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- Typical Dose
- 20-30 mcg
- 250–500 mcg
- Frequency
- 10 days per month (Khavinson protocol)
- 1–3 times daily
- Key Benefits
- 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
- 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
- Side Effects
- Injection site reactions
- Mild fatigue initially as immune system activates
- Mild sedation at higher doses (paradoxical)
- Fatigue (rare)
- Irritability during discontinuation (uncommon)
- Stacks With
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