Selank vs Semax — Reference Comparison Card
Selank (GABA-A modulation, anxiolytic, 250–500mcg intranasal) and Semax (BDNF upregulation, cognitive activating, 300–600mcg intranasal) — both Russian-developed, licensed in Russia, research chemicals in the West.
| Measure | Value | Unit | Notes |
|---|---|---|---|
| Selank Evidence Grade | B/C | grade | Grade B by Russian clinical standards (licensed anxiolytic/nootropic); Grade C by Western peer-review standards |
| Semax Evidence Grade | B/C | grade | Grade B by Russian clinical standards (licensed for stroke/TIA); Grade C by Western peer-review standards |
| Selank Standard Dose | 250–500 | mcg/dose | Intranasal; 2–3 drops per nostril × 2 daily from 0.15% solution; ~25mcg/drop |
| Semax Standard Dose | 300–600 | mcg/day | Intranasal; divided into 2–3 doses from 0.1% or 1% solution |
| Selank Sequence Length | 7 | amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro; tuftsin analogue |
| Semax Sequence Length | 7 | amino acids | Met-Glu-His-Phe-Pro-Gly-Pro; ACTH(4-7) analogue |
| BDNF Effect — Semax | 15–20 | minutes to BDNF onset | PMID 18457799: BDNF mRNA upregulation in rat hippocampus; Selank also shows BDNF effect but secondary to GABA-A |
Selank vs Semax — Reference Comparison
Both Selank and Semax are Russian-origin heptapeptides developed at the Institute of Molecular Genetics in Moscow, licensed in Russia, and classified as research chemicals outside Russia. Despite their structural similarity (both are 7 amino acid intranasal peptides), they have distinct pharmacological profiles and clinical applications.
Primary Comparison Table
| Feature | Selank | Semax |
|---|---|---|
| Full sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Met-Glu-His-Phe-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | ACTH(4-7) (Met-Glu-His-Phe) |
| Primary mechanism | GABA-A receptor modulation | BDNF upregulation via MC4R/CREB |
| Primary indication | Anxiolytic / mood stabilization | Cognitive activation / neuroprotection |
| Subjective character | Calming, anti-anxiety | Activating, focused |
| Russian approval | Yes — anxiolytic/nootropic | Yes — ischemic stroke/TIA |
| Evidence grade (Russian) | B | B |
| Evidence grade (Western) | C | C |
| Standard dose | 250–500mcg per dose | 300–600mcg/day |
| Route | Intranasal (primary) | Intranasal (primary) |
| Onset | 30–60 min (subjective) | 20–60 min (subjective); BDNF 15–20 min |
| Duration | 4–6 hours (reported) | 4–8 hours (reported) |
Mechanism Comparison Table
| Mechanism | Selank | Semax |
|---|---|---|
| GABA-A modulation | Primary anxiolytic mechanism | Weak / secondary |
| BDNF upregulation | Secondary; modest | Primary; rapid onset (PMID 18457799) |
| Serotonin modulation | Yes — mood stabilization | Mild |
| Dopaminergic effects | Weak | Moderate (proposed — focus effects) |
| Cholinergic effects | Mild | Moderate |
| Anti-inflammatory | Yes — IL-6, TNF-α reduction (rodent) | Yes — neuroprotective context |
| Immunomodulatory | Yes — tuftsin lineage | Mild |
Indication and Use Case Table
| Scenario | Recommended | Reason |
|---|---|---|
| Generalized anxiety | Selank | Primary anxiolytic mechanism; GABA-A modulation |
| Pre-performance focus | Semax | Cognitive activating; BDNF-mediated |
| Cognitive work / study | Semax | Attention and focus; neuroprotection |
| Sleep-adjacent use | Selank (low dose) | Calming effect; not sedating but compatible with sleep preparation |
| Combined use | Selank + Semax | Complementary; anxiety reduction + cognitive activation |
| Post-stroke recovery | Semax | Russian-licensed indication; clinical data |
| Anxiety with cognitive impairment | Selank + Semax | Both mechanisms relevant; no formal combination protocol |
Legal Status by Jurisdiction
| Jurisdiction | Selank | Semax |
|---|---|---|
| Russia | Licensed prescription (anxiolytic/nootropic) | Licensed prescription (stroke/TIA) |
| USA | Research chemical (unscheduled) | Research chemical (unscheduled) |
| UK | Not scheduled; legal to possess | Not scheduled; legal to possess |
| Australia | Not TGA-listed; gray area import | Not TGA-listed; gray area import |
| Canada | Gray market; no DIN | Gray market; no DIN |
| EU | Not EMA-approved; varies by member state | Not EMA-approved; varies by member state |
Evidence Grade Callout
Both peptides: Grade B by Russian standards, Grade C by Western standards. Russian licensing is real and based on controlled trial data, but most of that data is published in Russian-language journals not accessible or peer-reviewed by Western standards. Independent replication in Western peer-reviewed journals is largely absent. Decisions to use either compound should account for this evidence gap.
Legal Disclaimer
Neither Selank nor Semax is approved by the FDA, EMA, TGA, or Health Canada. Outside Russia and select Eastern European countries, both are research chemicals. Administration to humans outside approved clinical contexts is not supported by Western regulatory frameworks. This reference card is for educational purposes and does not constitute medical advice.
Related Pages
Sources
- Semenova TP et al. Effects of Selank on monoamine metabolism in rat brain. Zh Vyssh Nerv Deiat. 2009;59(4):469-76. PMID 19827524
- Agapova TY et al. Effects of Semax on the BDNF system in rat brain. Bull Exp Biol Med. 2007;144(5):636-40. PMID 18457799
- Kolomin T et al. Neuroprotective effects of Semax and C-terminal fragment Pro-Gly-Pro. Neural Plast. 2013;2013:352976. PMID 24307957
Frequently Asked Questions
Should I use Selank or Semax?
The choice depends on your primary goal. Selank is primarily anxiolytic: it reduces anxiety and promotes calm without sedation, via GABA-A receptor modulation. If anxiety, stress, or racing thoughts are the primary concern, Selank is the more appropriate choice. Semax is primarily cognitive-activating: it enhances focus and mental energy, upregulates BDNF, and is licensed in Russia for post-stroke cognitive recovery. If focus, learning, and mental activation are the goal, Semax is more appropriate. They are sometimes used together for complementary effects.
Can Selank and Semax be used together?
Russian clinical practice and anecdotal reports suggest Selank and Semax can be used together, with Selank attenuating the overstimulating effects of Semax and Semax offsetting any excess sedation from Selank. There is no peer-reviewed human safety data on the combination. The combination is not a licensed protocol in Russia; it represents off-label or research-level use. No pharmacokinetic or pharmacodynamic interaction studies have been conducted.
What does 'intranasal' mean for these peptides?
Intranasal administration means the peptide solution is applied as drops or spray to the nasal mucosa. The nasal cavity contains a dense vascular bed and proximity to the olfactory nerves, allowing peptides to partially bypass the blood-brain barrier via the olfactory-CNS route. For both Selank and Semax, this is the primary delivery route used in Russian clinical practice. Bioavailability via intranasal route is significantly higher than oral for these short peptides, which are degraded in the GI tract.