The published Semax dosage figures are real, specific, and much larger than most charts imply. The Russian stroke trial reported 12 to 18 milligrams a day, in an acute hospital setting.
The short version
Gusev and colleagues reported 12 mg a day for moderate stroke and 18 mg a day for severe stroke, over 5- and 10-day courses. The registered 1% nasal solution holds 500 µg per drop. Its label reaches 20,000 µg a day at the top. These are acute stroke figures.
Semax is a synthetic fragment of ACTH, residues 4 to 10, with a proline-glycine-proline tail added for stability. Russia registered it. Nowhere else did. Everything below is what that registration and its supporting trials put on record.
What the Semax studies administered
| Study | Species | Dose | Route | Duration | n |
|---|---|---|---|---|---|
| Gusev et al., 1997 | Human (acute hemispheric ischemic stroke) | 12 mg/day (moderate); 18 mg/day (severe) | Not stated in the record | 5 and 10 days | 30 treated, 80 control |
| Gusev et al., 2018 | Human (ischemic stroke, several stages) | 6,000 µg/day | Not stated in the record | Two 10-day courses, 20 days apart | 110 |
| Russian 1% label | Human (acute ischemic stroke) | 500 µg per drop; 6,000–20,000 µg/day by severity | Intranasal | 10 days | — |
| Russian 0.1% label | Human | 50 µg per drop | Intranasal | 10–14 days | — |
| Svishcheva et al., 2021 | Rat (restraint stress) | 5 to 450 µg/kg | — | — | — |
| Elagina et al., 2020 | Rat (diabetes, lipid metabolism) | 200 µg/kg | — | — | — |
| Inozemtseva et al., 2024 | Rat (chronic stress) | 60 nmol/kg per day | — | — | — |
A dash means we have no sourced figure for that cell and have not estimated one.
The route column carries two “not stated” entries on purpose. Both stroke reports give a daily amount without naming a route in the record we could reach. The registered product is intranasal, but we are not going to attribute that to a paper that did not say it.
The scale nobody mentions
Twelve milligrams a day is a large number for a peptide. Hold it against the vial a research buyer is looking at.
A standard Semax research vial holds 10 mg. The moderate-stroke figure from the 1997 report would consume more than one such vial per day, for five days.
The most effective daily doses were 12 mg for patients with strokes of moderate severity and 18 mg for patients with severe strokes (treatment course — 5 and 10 days).
Gusev et al., Zhurnal Nevrologii i Psikhiatrii, 1997That is the sentence the charts are built on, and it describes acute stroke care in hospital. It was never a cognition protocol.
Standard regimen of semax included 2 courses (6000 mcg/day) for 10 days with 20 day interval.
Gusev et al., Zhurnal Nevrologii i Psikhiatrii, 2018The 2018 follow-up therefore used half the 1997 moderate figure, in two short courses rather than one. Twenty-one years apart, same group, same indication, a two-fold difference. That is what an unsettled dose looks like even when the numbers are published.
Every human Semax figure is a stroke figure. Both reports are about the acute period after an ischemic stroke, in hospital, over courses of five or ten days. The searches that bring people to this compound are mostly about focus and memory. No published human study measured that, at any amount, so there is no dose to report for it.
Semax
The heptapeptide behind the Russian stroke literature reviewed here. Research use only — supplied with a batch-matched certificate of analysis.
Two registered strengths, ten times apart
Russia registers Semax at two concentrations, and confusing them is the most common error in anything written about it.
- 0.1% nasal drops. 50 µg per drop. Indicated for post-stroke recovery, encephalopathy, transient ischemic attack and optic nerve conditions.
- 1% nasal drops. 500 µg per drop, ten times stronger. Indicated specifically for the acute period of ischemic stroke.
The 1% label's directions are arithmetically consistent with its own per-drop figure: 2 to 3 drops per nostril, 3 to 4 times daily, gives 6,000 to 12,000 µg a day for moderate cases, and 12,000 to 20,000 µg for severe ones, over ten days.
We do not publish a daily total for the 0.1% product. The figures in circulation for it do not reconcile with 50 µg per drop, so one of the two is wrong and we cannot tell which.
The animal doses are micrograms per kilogram
The rodent literature runs from about 5 to 450 µg/kg. Elagina and colleagues used 200 µg/kg in a diabetic lipid model; Inozemtseva and colleagues used 60 nmol/kg a day in chronic stress.
For a 70 kg adult, 200 µg/kg by naive body-weight multiplication would be 14 mg, which happens to land near the human stroke figure. That coincidence is not a validation of the method. Surface-area scaling divides a rat dose by 6.2, and the two numbers agreeing once does not make multiplication correct.
- The 1997 report gives a daily amount in milligrams, by severity tier, for acute stroke.
- The registered labels give micrograms per drop, at two strengths that differ tenfold.
- The rodent studies give micrograms per kilogram, which is a third kind of number again.
What if you already have a number?
Semax figures vary by a factor of a hundred depending on whether the source meant the 0.1% product, the 1% product, or a rat.
Turning a figure into a syringe volume is arithmetic, and the peptide calculator does it from the vial strength and the volume of diluent. That part always works.
Which is the trap. A calculator converts an unsourced number as cleanly as a sourced one. The output looks equally precise either way. Check which one your number came from before you convert it.
What is checkable
Identity and purity, as always, and here it matters more than usual because the quantities involved are large. A 10 mg vial is a single acute-stroke day at the 1997 moderate figure, so a purity shortfall is a proportionally large absolute shortfall.
How to read a COA, the complete guide, the stroke research and where to buy Semax cover the rest. The peptide dosage chart sets it against the library.
Semax
Research-use-only material, sold by the vial with batch documentation. Check the certificate of analysis against the batch you receive.
What to know now
- The 1997 stroke report gives 12 mg/day for moderate and 18 mg/day for severe strokes, over 5- and 10-day courses, in 30 treated patients against 80 controls.
- The 2018 follow-up used 6,000 µg a day in two 10-day courses, in 110 patients.
- The registered 1% nasal solution is 500 µg per drop; the 0.1% is 50 µg.
- Neither stroke report states a route in the record, so we do not attribute one.
- Every human figure here is acute stroke care. None of it was a cognition protocol.
What we're watching
Semax has the opposite problem to most compounds here: real human numbers, in a language and a registration system the rest of the world does not read. A replication outside Russia would be the single most valuable study anyone could run on it.
We would also welcome a full text of the 1997 report. The route is the one thing the reachable record leaves open, and it is not a small gap.
Frequently asked questions
What dose of Semax was used in the stroke trial?
Gusev and colleagues reported 12 mg a day for strokes of moderate severity and 18 mg a day for severe strokes, over courses of 5 and 10 days respectively, in 30 treated patients against 80 controls.
What is the strength of the Russian Semax product?
Two strengths are registered. The 0.1% nasal drops contain 50 µg of Semax per drop. The 1% nasal drops, indicated for acute ischemic stroke, contain 500 µg per drop.
How much Semax does the 1% label direct in a day?
For moderate stroke the label directs 2 to 3 drops in each nostril, 3 to 4 times a day, which comes to 6,000 to 12,000 µg daily over 10 days. For severe stroke it rises to 12,000 to 20,000 µg.
Is Semax approved outside Russia?
No. It is registered in Russia for stroke, post-stroke recovery, transient ischemic attack and optic nerve conditions. It has no FDA approval and no marketing authorization elsewhere.
What doses did the Semax animal studies use?
Micrograms per kilogram. The rat work spans roughly 5 to 450 µg/kg, with 200 µg/kg in the diabetic lipid study and 60 nmol/kg per day in the chronic stress model.
References
- Gusev, E. I., Skvortsova, V. I., Miasoedov, N. F., et al. (1997). Effectiveness of Semax in acute period of hemispheric ischemic stroke (a clinical and electrophysiological study). Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 97(6), 26–34. PubMed search PMID ?term=Gusev+Semax+acute+ischemic+stroke+1997
- Gusev, E. I., Martynov, M. Y., Kostenko, E. V., et al. (2018). The efficacy of semax in the treatment of patients at different stages of ischemic stroke. Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 118(3, Vyp. 2), 61–68. https://doi.org/10.17116/jnevro20181183261-68
- Russian State Register of Medicines (RLS). Semax 1% nasal drops — registered product instruction. https://www.rlsnet.ru/tn_index_id_5678.htm
- Vidal Russia. Semax 0.1% nasal drops — registered product instruction. https://www.vidal.ru/drugs/semax__28676
- Svishcheva, M. V., Mishina, Y. S., Medvedeva, O. A., et al. (2021). Morphofunctional state of the large intestine in rats under conditions of restraint stress and administration of peptide ACTH-PGP (Semax). Bulletin of Experimental Biology and Medicine, 170(3), 384–388. https://doi.org/10.1007/s10517-021-05072-z
- Elagina, A. A., Lyashev, Y. D., Lyashev, A. Y., et al. (2020). Correction of lipid metabolism disorders in diabetes mellitus with peptide drugs. Bulletin of Experimental Biology and Medicine, 168(5), 618–620. https://doi.org/10.1007/s10517-020-04764-2
- Inozemtseva, L. S., Yatsenko, K. A., Glazova, N. Y., et al. (2024). Antidepressant-like and antistress effects of the ACTH(4-10) synthetic analogs Semax and Melanotan II on male rats in a model of chronic unpredictable stress. European Journal of Pharmacology, 984, 177068. https://doi.org/10.1016/j.ejphar.2024.177068
- Panikratova, Y. R., Lebedeva, I. S., Sokolov, O. Y., et al. (2020). Functional connectomic approach to studying Selank and Semax effects. Doklady Biological Sciences, 490(1), 9–11. https://doi.org/10.1134/S001249662001007X
Both stroke reports give a daily amount without naming a route in the record we could reach, so the route column carries no entry for them.