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Thymulin vs Semax & Selank

A detailed comparison to help you understand the differences and choose the right peptide for your research goals.

Thymulin

Thymulin (Facteur Thymique Sérique) is a zinc-dependent nonapeptide hormone produced by thymic epithelial cells. It plays important roles in T-cell differentiation and immune system maturation.

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Semax & Selank

A nootropic combination pairing two Russian-developed peptides for cognitive enhancement. Semax provides stimulating focus and neuroprotection while Selank offers anxiolytic and mood-stabilizing effects, creating a balanced cognitive enhancement stack.

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Side-by-Side Comparison

AspectThymulinSemax & Selank
MechanismRequires zinc for biological activity. Promotes T-cell differentiation, modulates cytokine production, and influences neuroendocrine function. Levels decline significantly with age.Semax enhances BDNF expression and modulates dopamine and serotonin systems for improved focus, memory, and neuroprotection. Selank affects BDNF and GABA systems, providing anxiolytic effects and immune modulation. Together they support cognitive function while managing stress and anxiety.
Typical DosageResearch protocols vary. Often studied alongside zinc supplementation. Typical research doses in the microgram range.Semax: 200-600mcg intranasally 2-3 times daily. Selank: 250-500mcg intranasally 2-3 times daily. Can be used together or alternated based on needs.
AdministrationSubcutaneous or intramuscular injection in research settings. Requires adequate zinc status for activity.Primarily administered intranasally for rapid brain uptake. N-Acetyl versions (NA-Semax, NA-Selank) offer enhanced stability and potency. Can also be injected subcutaneously.
Side EffectsLimited data on exogenous administration. Theoretical effects on immune function require monitoring.Semax may cause mild irritability or hair shedding. Selank may cause mild fatigue or nasal irritation. Both are generally well-tolerated.
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Key Differences

Unique to Thymulin:

Unique to Semax & Selank:

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