Cognitive Duo
Two-peptide cognitive stack pairing the nootropics Semax and Selank. Short 4-week cycle (Semax/Selank are cycled 10–30 days on, then 1–2 weeks off).
Model levels over time
% of sampled peakModel details: Semax · relative timing
Compare timing and buildup for this compound. The values are not blood concentrations or a measure of strength.
Shows a relative timing scenario; absolute blood concentrations are not calibrated.
Timing assumptions and sources
Legacy 0.48 h is an assumption, not measured human systemic half-life. Brain residence or 4–8 h effects must not be substituted for blood elimination.
One 1 mg input peaks at 1 relative unit after a single dose. Other amounts scale proportionally; overlapping doses add when accumulation is on. Different compounds use separate relative scales.
- Timing half-life used
- 0.48 hours
- Absorption half-life assumed
- 0.12 hours
- Reference amount for the relative scale
- 1 mg
- Absorption half-life is assumed to be one quarter of the slower timescale (0.12 h); it is not a measured absorption parameter.
- A single 1-unit input has a peak of 1 relative unit; scaling and repeated-dose addition are mathematical assumptions. This normalization is independent of the example dose.
- Species/route and parent/metabolite separation remain unresolved for absolute exposure.
- Do not import enkephalin half-life from enzyme-inhibition experiments.
- Semax, an ACTH(4-10) analogue with nootropic properties, activates dopaminergic and serotoninergic brain systems in rodents.
Legacy 0.48 h is an assumption, not measured human systemic half-life. Brain residence or 4–8 h effects must not be substituted for blood elimination.
- Shevchenko et al.2006, labeled peptide biodegradation
Semax degrades toHFPGP andPGP in nerve-cell work; do not combine parent and metabolite exposure.
semax-relative-timing-2026-10 · version 1
Model details: Selank · relative timing
Compare timing and buildup for this compound. The values are not blood concentrations or a measure of strength.
Shows a relative timing scenario; absolute blood concentrations are not calibrated.
Timing assumptions and sources
Legacy 0.48 h is unverified; enkephalin half-life is explicitly a different molecule.
One 1 mg input peaks at 1 relative unit after a single dose. Other amounts scale proportionally; overlapping doses add when accumulation is on. Different compounds use separate relative scales.
- Timing half-life used
- 0.48 hours
- Absorption half-life assumed
- 0.12 hours
- Reference amount for the relative scale
- 1 mg
- Absorption half-life is assumed to be one quarter of the slower timescale (0.12 h); it is not a measured absorption parameter.
- A single 1-unit input has a peak of 1 relative unit; scaling and repeated-dose addition are mathematical assumptions. This normalization is independent of the example dose.
- Do not interpret inhibited leu-enkephalin degradation as Selank elimination.
- Intranasal rat brain distribution does not calibrate human SC plasma.
- [Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia].
Legacy 0.48 h is unverified; enkephalin half-life is explicitly a different molecule.
- Shevchenko et al.2006, labeled peptide biodegradation
Identified Selank metabolites; rat brain intranasal work, no human calibration in inspected abstract.
- Selank enkephalin-degradation experiment
Half-life is that of leu-enkephalin, not Selank.
selank-relative-timing-2026-10 · version 1
Different scales · each curve is normalized to its own peak. Compare timing and shape, not concentration or potency.
| Date | Semax · Relative timing (% of sampled peak) | Selank · Relative timing (% of sampled peak) |
|---|---|---|
| W1 | 0 % of sampled peak | 0 % of sampled peak |
| W1 | 0.00291908 % of sampled peak | 0.00291908 % of sampled peak |
| W1 | 1.35087 % of sampled peak | 1.35087 % of sampled peak |
| W2 | 0.00000630776 % of sampled peak | 0.00000630776 % of sampled peak |
| W2 | 0.00291908 % of sampled peak | 0.00291908 % of sampled peak |
| W2 | 1.35087 % of sampled peak | 1.35087 % of sampled peak |
| W3 | 0.00000630776 % of sampled peak | 0.00000630776 % of sampled peak |
| W3 | 0.00291908 % of sampled peak | 0.00291908 % of sampled peak |
| W3 | 1.35087 % of sampled peak | 1.35087 % of sampled peak |
| W4 | 0.00000630776 % of sampled peak | 0.00000630776 % of sampled peak |
| W4 | 0.00291908 % of sampled peak | 0.00291908 % of sampled peak |
| W4 | 1.35087 % of sampled peak | 1.35087 % of sampled peak |
| W5 | 0.00000630776 % of sampled peak | 0.00000630776 % of sampled peak |
The chart uses a bounded time grid. Long horizons can miss brief peaks between samples; shorten the horizon to inspect more detail. Chart peaks are sampled values.
Protocol summary
Cognitive Duo · 4 weeks starting Oct 15, 26
- Semax — 300 mcg 2 times per day, weeks 0–4
- Selank — 250 mcg 2 times per day, weeks 0–4
Protocol overview
- Category
- peptide stack
- Duration
- 4 weeks
- Compounds
- 2
- Tags
- cognitive, semax, selank, duo, peptide
Compounds in this protocol
How to read this protocol
The chart shows available model curves over the 4-week example. Rows whose model is unavailable are retained for context but produce no curve. Read each model’s details for what its line represents; a plotted level does not predict treatment effects or establish a suitable dose.
The peak/trough explorer examines one complete model interval. The single-dose decline explorer is a separate one-dose scenario; it does not calculate this protocol's washout or a safe treatment-change date. The compound comparison shows available model outputs, not equivalent clinical effects.
Educational only. Not medical advice. These examples do not predict individual blood levels.