Thymulin vs Semax
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.
- Semax is a synthetic heptapeptide derived from ACTH developed in Russia. It is a potent nootropic that enhances memory, focus, and provides neuroprotection. Approved in Russia for cognitive disorders, stroke recovery, and traumatic brain injury.
- Half-Life
- ~30 minutes active half-life
- Minutes (but effects persist for hours via BDNF induction)
- Admin Route
- SubQ
- Intranasal, SubQ
- Research
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- Typical Dose
- 20-30 mcg
- 0.25–1 mg (250–1000 mcg)
- Frequency
- 10 days per month (Khavinson protocol)
- 1–2 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
- Enhances memory and learning
- Improves focus and concentration
- Increases mental energy and motivation
- Provides neuroprotection via BDNF and NGF upregulation
- Reduces cognitive decline
- May alleviate ADHD symptoms
- Supports recovery from brain injury and stroke
- Fast-acting — effects within 30–60 minutes
- Approved in Russia for cognitive disorders and stroke recovery
- Side Effects
- Injection site reactions
- Mild fatigue initially as immune system activates
- Headache (rare, often from higher doses)
- Anxiety or overstimulation at high doses
- Sleep disruption if dosed too late
- Irritability (uncommon)
- Stacks With
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