⚖ Head-to-Head · Cognitive Peptides

Semax vs Selank

Mechanism, half-life, dosing & research status compared side-by-side.

Semax
Cognitive & Nootropic
Not Approved
CognitiveNeuroprotectionNootropicBDNF
Semax is a synthetic heptapeptide analog of the ACTH(4-10) fragment, developed in Russia in the 1980s by the Institute of Molecular Genetics. It is approved as a pharmaceutical drug in Russia for cognitive impairment, is…
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Selank
Cognitive & Anxiolytic
Not Approved
CognitiveAnxiolyticNootropicImmune
Selank is a synthetic analog of the immunomodulatory tetrapeptide tuftsin (Thr-Lys-Pro-Arg), extended with Pro-Gly-Pro for metabolic stability. Developed at the Institute of Molecular Genetics in Russia, it is approved a…
Full Selank profile →
Technical Specs Comparison
MetricSemaxSelank
Research Status Extensively Studied Extensively Studied
Molecular Weight 813.9 Da 751.9 Da
Half-Life ~minutes (plasma); CNS effects 24h+ ~2 min (plasma); CNS effects 24h+
Peak Time ~30–60 min (intranasal) ~30 min (intranasal)
Typical Dose 300–900 µg intranasal 250–750 µg intranasal
Frequency Once or twice daily Once or twice daily
Route Intranasal (primary) / Subcutaneous Intranasal (primary) / Subcutaneous
Amino Acids 7 7
WADA Status Not Listed Not Listed
FDA Status Not Approved Not Approved
Stack Compatibility & Key Differences
Both are active research compounds. See individual pages for full protocol data.
PK Plotter · Visualize plasma levels over time
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Frequently Asked Questions
What is the difference between Semax and Selank?
Semax: Semax is a synthetic heptapeptide analog of the ACTH(4-10) fragment, developed in Russia in the 1980s by the Institute of Molecular Genetics. It is approved as a pharmaceutical drug in Russia for cognitive impairment, is… Selank: Selank is a synthetic analog of the immunomodulatory tetrapeptide tuftsin (Thr-Lys-Pro-Arg), extended with Pro-Gly-Pro for metabolic stability. Developed at the Institute of Molecular Genetics in Russia, it is approved a…
Can you stack Semax and Selank?
Both are active research compounds. See individual pages for full protocol data.
Which has a longer half-life, Semax or Selank?
Semax half-life: ~minutes (plasma); CNS effects 24h+. Selank half-life: ~2 min (plasma); CNS effects 24h+.
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Verified Scientific Data
All specifications on this page are sourced from peer-reviewed literature and primary research. Half-life values, dosing ranges, and mechanism data are cross-referenced against published studies. Last audited 2026-06-07.
● Peer-reviewed sources ● Audit timestamp: 2026-06-07 ● Data version: ASCEND Wiki 2026
Data sourced from ASCEND Wiki · Semax profile · Selank profile · All comparisons
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