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ToolsCompareSemax vs Thymulin

Semax vs Thymulin

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

Cognitive Enhancement
Semax
Immune Support
Thymulin
Summary
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.
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.
Half-Life
Minutes (but effects persist for hours via BDNF induction)
~30 minutes active half-life
Admin Route
Intranasal, SubQ
SubQ
Research
Typical Dose
0.25–1 mg (250–1000 mcg)
20-30 mcg
Frequency
1–2 times daily
10 days per month (Khavinson protocol)
Key Benefits
  • 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
  • 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
Side Effects
  • Headache (rare, often from higher doses)
  • Anxiety or overstimulation at high doses
  • Sleep disruption if dosed too late
  • Irritability (uncommon)
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With