The Cognitive Stack
The most potent nootropic peptide combination available. Semax boosts BDNF for neuroplasticity and focus. Selank provides anxiolytic calm without sedation. Dihexa is a research-stage peptide showing extraordinary potency for memory and synaptic formation.
Difficulty
advanced
Est. Cost
$150-350
Duration
2-4 weeks on, 2-4 weeks off
Peptides
3 compounds
Protocol
| Peptide | Dose | Frequency | Timing | Role |
|---|---|---|---|---|
| Semax | 200-600mcg | 1-2x daily | Morning and early afternoon (intranasal) | BDNF upregulation, focus enhancement, neuroprotection |
| Selank | 250-500mcg | 1-2x daily | Morning and early afternoon (intranasal) | Anxiolytic via GABA modulation, cognitive enhancement without sedation |
| Dihexa | 10-20mg | Once daily | Morning (oral) | Hepatocyte growth factor modulation for synaptogenesis and memory consolidation |
Notes
Semax and selank are Russian-developed peptides with decades of clinical use. Both are administered intranasally for direct brain access. Semax enhances focus through BDNF upregulation. Selank reduces anxiety through GABA modulation without the sedation of benzodiazepines. Dihexa is in the research-only category and is extraordinarily potent at promoting synapse formation (seven orders of magnitude more potent than BDNF in some assays). Due to limited human safety data on dihexa, this stack is for advanced users comfortable with research-grade compounds. Start with semax + selank only. Add dihexa only after assessing tolerance. N-Acetyl Semax Amidate (NASA) is a more potent, longer-lasting semax variant. Cycle all three to prevent tolerance.
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Written by Alejandro Reyes
Founder & Lead Researcher
Reviewed by Peptide Nerds Editorial · Updated March 2026
Medical Disclaimer: Peptide stacks are not FDA-approved protocols. This information is for educational purposes only. Consult a qualified healthcare provider before combining any peptides.