The Russian nootropic peptide used for focus, cognition, and neuroprotection — sister peptide to Selank with a stronger stimulating profile.
Semax is a synthetic 7 amino acid peptide developed at the Russian Academy of Sciences in the 1980s as a fragment analog of ACTH (4-10). In Russia it’s approved for stroke recovery, TIA, and cognitive disorders.
It’s considered a sister peptide to Selank — similar Russian origin and intranasal administration — but with a more stimulating, focus-enhancing profile rather than anxiolytic. Many users stack the two: Semax for cognition, Selank for stress buffering.
Not FDA approved. Not WADA prohibited. Available as research chemical or nasal spray formulation.
The core mechanism. Dolotov 2006 (PMID 16996037) measured raised BDNF and TrkB expression in rat hippocampus after intranasal Semax; Dmitrieva 2010 (PMID 19633950) and Shadrina 2010 (PMID 19662538) tracked neurotrophin and receptor transcription after cerebral ischaemia. Medvedeva 2014 (PMID 24661604), a genome-wide analysis in a rat stroke model, found Semax shifted expression across immune and vascular gene sets while suppressing inflammatory ones. Stavchansky 2011 (PMID 20617398) reported increased proliferative activity in rat brain tissue under experimental ischaemia.
Eremin 2005 (PMID 16362768) showed Semax activates dopaminergic and serotoninergic systems in rodents — but the important detail is how. Semax does not itself spike dopamine; it potentiates release driven by other stimuli. That is the pharmacological basis for the common user report that caffeine feels stronger on Semax, and the reason it does not behave like a stimulant on its own.
Like Selank, inhibits enkephalin breakdown — contributes to stress tolerance and mild analgesic properties.
Reduces ischemic damage in stroke models; this is why it’s approved in Russia for acute stroke and TIA protocols.
| Benefit | Evidence |
|---|---|
| Focus & attention | The most-reported effect by users, and the least directly measured. The underlying pharmacology is real (below), but there is no placebo-controlled Western trial of Semax for attention in healthy adults |
| Learning / memory | Mechanistically supported in animals, thinly in humans. Dolotov 2006 (PMID 16996037) showed intranasal Semax raises BDNF and TrkB expression in rat hippocampus with improved learning task performance. No Western human cognition trial exists |
| Stroke recovery | The best-evidenced use, and the reason the compound exists. Gusev 2018 (PMID 29798983) followed 110 post-stroke patients given two 10-day courses of 6,000 mcg/day intranasally with a 20-day interval. Plasma BDNF rose and stayed elevated throughout, Barthel index improvement accelerated, and BDNF levels correlated with Barthel score. An earlier Gusev trial covered the acute phase of hemispheric ischaemic stroke (PMID 11517472) |
| ADHD-like symptoms | Anecdotal improvements in focus, task-switching, motivation |
| Mood | Mild mood elevation; not an antidepressant but a useful adjunct |
| Eye strain / recovery | A registered Russian indication (optic nerve disease), supported by Russian clinical data we cannot independently assess — no indexed Western trial |
One caveat governs this whole page: every human study of Semax is Russian. It has been prescribed there since the 1990s and sits on the Russian List of Vital and Essential Drugs, which is a genuine signal — but there is no Western clinical trial of Semax for any indication, the trials are small by regulatory standards, and long-term safety has not been established to Western standards.
That cuts both ways. It is not grounds for dismissing the compound: three decades of clinical use without a notable safety signal is meaningful evidence. It is grounds for not treating the stroke data as though it were an FDA-registration package.
One nuance the enthusiast write-ups usually drop: Semax is described as anxiolytic, but the effect is dose-dependent and can invert. Higher doses have been reported to be anxiogenic in behavioural work, which matches the user reports of irritability and restlessness at the top of the range. If you feel wired rather than clear, the dose is the first thing to look at.
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeNot medical advice. These figures describe what is reported in the literature and what practitioners and communities do — not a recommendation, and for most compounds here no human dose-finding study exists. Talk to a qualified healthcare provider.
Both published human doses are intranasal. The stroke trial (Gusev 2018, PMID 29798983) used 6,000 mcg/day in two 10-day courses separated by a 20-day interval. A cognitive-performance study used a single 1,000 mcg dose. Animal work has run 50–600 mcg/kg intranasally.
Nothing establishes a dose for daily cognitive use, and note that the clinical stroke dose is roughly ten times the practical range below — the gap between the trial protocol and everyday use is unusually wide for this compound.
This is the band practitioner protocols and course material converge on. Higher figures circulate — up to 1,000 mcg per dose several times a day — but nothing establishes that more is better for daily cognitive use, and the range above is where documented practice sits.
Subcutaneous dosing is common in practice and gives more precise control than a nasal pump. The efficacy evidence, though, is intranasal: both Gusev stroke trials and the cognitive study used that route, and the Russian registered product is a nasal solution.
One human study did use injection — Panikratova 2020 (PMID 32342318), the fMRI study of Semax and Selank on amygdala connectivity. So parenteral Semax is not unheard of in research; it is simply not where the clinical outcome data comes from. Treat SC as a route with mechanistic precedent but no efficacy trial behind it, and do not assume the two routes are equivalent milligram for milligram.
Typical use is 10–30 day cycles followed by 1–2 week breaks. Some users run longer continuous cycles without tolerance issues.
Not medical advice. These figures describe what is reported in the literature and what practitioners and communities do — not a recommendation, and for most compounds here no human dose-finding study exists. Talk to a qualified healthcare provider.
A nasal pump delivers roughly 100 µL per spray, so the concentration sets your per-spray dose.
For the 200–600 mcg/day range, dilute for control: 10 mg vial + 5 mL BAC water = 2 mg/mL = 200 mcg per spray. One spray = 200 mcg, three = 600 mcg — the whole range in whole sprays.
A 30 mg vial in 5 mL gives 6 mg/mL = 600 mcg per spray, which puts an entire day at the top of the range in a single spray and leaves no room to titrate. Use more diluent, or a larger bottle, if you want finer steps.
Pre-filled with a typical Semax setup. Edit any field — the draw updates live.
Insulin syringe — 100 units = 1 mL
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Semax is sold for research use only. If you are sourcing it for research, we recommend Lyvn — every batch third-party tested with the full laboratory panel published on the product page.
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For research use only. Not for human consumption. 21+.
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeNo. Semax is a Russian-developed synthetic heptapeptide (a Pro-Gly-Pro–extended fragment of ACTH(4-10)) that has never been approved by the FDA, EMA, or any Western regulatory authority. Russia approved it as a nootropic (0.1% intranasal) and for acute ischemic stroke (1% intranasal). In the US it is sold only as a research chemical.
Russian-clinic protocols: 0.1% intranasal drops (1 mg/mL) for cognitive/asthenia use; 1% drops (10 mg/mL) for acute stroke at 6000 mcg/day in 10-day courses with 20-day washouts. This guide uses 200–600 mcg/day total, once or twice daily, which is where practitioner protocols and course material converge. Higher figures circulate — up to 1,000 mcg per dose several times daily — but nothing establishes that more is better for daily cognitive use, and the top of that range starts overlapping the Russian stroke-indication dose.
Primary route is intranasal. A 5 mg lyophilized vial + 2 mL bacteriostatic water yields 2.5 mg/mL — at 100 mcL per spray, that delivers 250 mcg per spray. Subcutaneous administration (300–600 mcg/day) is community practice with no clinical-evidence base behind it.
Onset is reported within 15–30 minutes intranasally; subjective effects (focus, mental clarity) sustain 3–6 hours per dose. Animal data (Shevchenko 2006 PMID 16523722) shows brain detection within ~2 minutes of intranasal dosing, with downstream gene-expression effects within ~30 minutes (glial culture) peaking ~1.5 hours in vivo.
Both are Russian Pro-Gly-Pro–stabilized peptides, but they hit different physiology. Semax is derived from ACTH(4-10) and is reported as more stimulant/focus-promoting — closer to a "smart drug" profile. Selank is derived from tuftsin and is reported as more anxiolytic/calming. Community users often stack the two. Neither has Western clinical-trial validation in any of these uses.
Not specifically named on the WADA Prohibited List as of 2025–2026. WADA reserves discretion to sweep peptides under broad class language (S0 — Non-Approved Substances). Competitive athletes should verify the current-year list before use.
Disclaimer: This guide is for educational and informational purposes only and is not intended as medical advice, diagnosis, or treatment. The compounds discussed are not FDA approved for human use. Always consult a qualified healthcare provider before starting any new supplement or peptide protocol. StackTrax does not sell peptides or supplements directly — purchase links go to third-party vendors. StackTrax is not responsible for the products, quality, or business practices of any third-party vendor.
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StackTrax guides cover peptides and compounds that are not FDA-approved for the uses discussed. The dosing, reconstitution, and safety information is compiled from published research and community protocols for educational purposes only.
Before using any compound mentioned here, consult a qualified healthcare provider. StackTrax does not sell, prescribe, or recommend these substances for personal use.