The protocol at a glance
The Russian label gives nasal drops in short courses of 3 to 14 days. The stronger 1% drops are for hospital stroke care and run for 10 days.
| Use (Russian label or study) | Amount per day |
|---|---|
| 0.1% drops, adults (general) | 500 to 5,000 mcg a day, 3 to 5 days (can extend to 14) |
| 0.1% drops, optic nerve disease | 600 to 900 mcg a day, 7 to 10 days |
| 1% drops, acute stroke (moderate) | 6,000 to 12,000 mcg a day, 10 days |
| 1% drops, acute stroke (severe) | 12,000 to 20,000 mcg a day, 10 days |
| 1997 hospital stroke study | 12 mg a day (moderate) or 18 mg a day (severe), 5 or 10 days |
From the Russian drug reference RLS (Semax nasal drops entry; the insert it shows was approved in 2008, so it may not be the current one) and the 1997 study. Nasal use only. No label covers injections. Single doses on the 0.1% label range from 200 to 2,000 mcg.
Community notes report 200 to 600 mcg a day, 2 weeks on and 2 to 4 weeks off, mostly nasal and sometimes by injection. These are user reports, not trial data.
What people say they do, collected from community discussions. Not tested in a trial; shown so you can compare it with the evidence above.
Mixing
No mixing table here: this one is used as a capsule, nasal spray or skin product, or has no human amount to calculate from. The general mixing calculator works for any vial.
What the trials found
Human data is small and mostly Russian. None of the abstracts I read give effect sizes, and I found no large placebo-controlled trial. Two stroke studies:
Gusev EI et al., Zh Nevrol Psikhiatr Im S S Korsakova 2018 (PMID 29798983; two 10-day courses of 6,000 mcg a day, 20 days apart) and 1997 (PMID 11517472). Both are Russian-language papers with English abstracts.
Side effects
- The label lists mild nose irritation with long use.
- The label says not to use it in pregnancy, breastfeeding, acute psychosis, anxiety disorders or after past seizures.
- I found no large trial that measured safety.
How it works
ACTH fragment
Semax is built from a piece of ACTH (amino acids 4 to 10) with Pro-Gly-Pro added.
BDNF in rats
In rats, one dose raised BDNF protein 1.4-fold in the hippocampus and switched on its TrkB receptor.
Sources
- RLS (rlsnet.ru) Semax nasal drops entry, Peptogen; insert approved 2008
- Gusev EI et al. Zh Nevrol Psikhiatr 2018;118(3-2):61-68, PMID 29798983
- Gusev EI et al. Zh Nevrol Psikhiatr 1997;97(6):26-34, PMID 11517472
- Dolotov OV et al. Brain Res 2006, PMID 16996037
- ClinicalTrials.gov search by intervention name, run 5 Nov 2026: no Semax studies listed