Semax Dosage Chart.
Semax is a synthetic heptapeptide built from the ACTH(4-7) fragment, licensed as a stroke drug in Russia and sold everywhere else as a research nootropic. This chart gives you the doses people actually use, in syringe units, and is straight with you about which of those numbers came from a trial and which came from convention.
200–600 mcg per day, taken in the morning, with 300 mcg as the usual figure. On a 10 mg vial mixed with 2 mL of bacteriostatic water that is 4–12 units on a U-100 insulin syringe, and 300 mcg is 6 units. Research-community convention, not trial data.
This chart is the condensed version. For the full write-up (mechanism, the nasal-versus- injection question, stacking and vendor testing), read the full Semax dosing guide.
Dosage Protocols
Units assume a 10 mg vial reconstituted with 2 mL bacteriostatic water = 5,000 mcg/mL, so 1 unit on a U-100 syringe = 50 mcg. Different setup? Use the calculator. These microgram figures are convention; the doses studied in humans were milligrams, intranasal, in stroke patients.
Start here if you have never used Semax, and dose it before 10am for the first week.
Why this dose+
Two weeks at 200 mcg tells you whether you are a responder at all, and whether it costs you sleep. It is activating for most people who feel anything, so timing matters more than the amount at this stage. Reassess at two weeks before moving up.
The figure most protocols converge on, and the one to pick if you read only one line here.
Why this dose+
Take the optional sixth day and the week comes to 1,800 mcg. This range is convention, not a finding: no published human study has used a dose near it for cognitive purposes. It splits the difference between milligram stroke dosing and something sensible to take daily.
The top of conventional use, split into two doses because activation, not the milligrams, is the limit.
Why this dose+
Nothing above this has any basis outside acute stroke care, where the doses were milligrams given intranasally in hospital. If you are at 600 mcg and still feel nothing, the honest read is non-responder rather than a reason to go higher.
- Semax is sold in Russia as 0.1% nasal drops; every human trial used intranasal or IV dosing.
- Rat data: intranasal Semax reaches brain tissue within 2 minutes, then degrades fast.
- No human study has ever tested the subcutaneous route these vials are sold for.
- Want the route with evidence behind it? Reconstitute the vial and dose it intranasally.
- 12 to 18 mg/day was intranasal or IV, in hospitalised stroke patients, for 5 to 10 days.
- That is a rescue protocol, not headroom above a 300 mcg cognitive dose.
- No dose-response curve for Semax exists in a healthy person, by any route.
- Find the smallest dose you actually notice, and stop there.
Weekly Schedule
All three tiers front-load the week and protect sleep. Dose on waking; if you split the upper-end tier, the second dose goes no later than early afternoon.
Missed a morning? Skip it rather than dosing in the afternoon to catch up; a late dose costs you the night. Keep the pattern identical week to week, because the off days are the only check you have on whether it is doing anything.
Semax Reconstitution Calculator
Enter your vial size, how much water you added, and the dose you want. We'll tell you exactly how much to draw. A 10 mg vial with 2 mL of bacteriostatic water gives 5,000 mcg/mL, which puts a 300 mcg dose at 6 units on a U-100 syringe. Microgram doses draw small, so the calculator will warn you when a draw is too short to measure reliably.
Double-click a preset to edit it
Double-click a preset to edit it
Double-click a preset to edit it
Ultra-fine, best for small doses
Concentration
5.00 mg/mL
1 unit = 50 mcg
Draw volume
0.060 mL
= 300 mcg ÷ 5000 mcg/mL
Units to draw (0.3 mL syringe)
6.0 units
0.3 mL Syringe
6.0 IUFrom Vial to Dose in 6 Steps
Alcohol swab the Semax vial and the bacteriostatic water vial, and let both air-dry before you pierce them.
Run the bacteriostatic water down the inside wall of the 10 mg vial. Never squirt it directly onto the powder cake.
Roll the vial gently until it turns completely clear. Shaking damages the peptide, and there is no reason to rush a step that takes thirty seconds.
Use a fresh U-100 insulin syringe and the calculator. At 5,000 mcg/mL, 200 mcg is 4 units, 300 mcg is 6 units and 600 mcg is 12 units.
People inject subcutaneously into the abdomen or thigh, rotating sites. Worth repeating: every human trial of Semax used intranasal drops or IV infusion, so if you want the route with evidence behind it, dose the same reconstituted solution intranasally instead: a few drops per nostril, split between the two, head level rather than tipped back.
Keep the powder refrigerated and the mixed vial at 2–8 °C, and never freeze the solution. Treat roughly 4 weeks as the outside limit once mixed; that figure comes from the benzyl-alcohol preservative in bacteriostatic water, not from a published Semax stability study. Needles go in a sharps container.
One 10 mg vial is 33 doses at 300 mcg, which runs well past the roughly 4-week preservative window on a mixed vial, so on the standard tier you are pacing against the water, not the peptide. If a 10 mg vial is more than you will get through, mix half of it or buy the 5 mg size rather than stretching one vial across two months.
What to Expect
This timeline is short because the evidence is short. Everything below is either a measured finding or an explicit gap; we have not filled the gaps with things that sound plausible.
Rat data shows intranasal Semax in brain tissue within 2 minutes of dosing, so if you are going to feel anything, it is soon. In humans nothing has ever been measured on this timescale. Self-reports cluster around a mild alertness or talkativeness shift, and a large fraction of people report nothing whatsoever. Both are normal.
The activating quality is the most consistently described effect and it shows up immediately, not gradually. This is also the window where the failure mode appears: dose it after midday and you will find out at 1am. If sleep suffers on day two, move the dose earlier before you touch the amount.
The Russian courses ran 10 days. The 2018 study of 110 stroke patients found plasma BDNF rose on a 6 mg/day regimen, but those were people recovering from a stroke, given a dose 20 times higher than community protocols, by a different route. That finding is real and it does not transfer to a healthy person injecting 300 mcg. If you are looking for the moment a cognitive effect is supposed to consolidate, no study has ever identified one.
The longest published regimens are 10-day courses, sometimes repeated after a 20-day break. Continuous daily use past that point has never been studied in anyone, which is why the protocols above cap out and build in real breaks.
No withdrawal syndrome has been described, and no study has tested whether anything persists after the last dose. If you noticed a genuine effect on-cycle, the off week is the only honest test of whether it was the peptide.
You are your own dataset here. The Russian stroke trials are genuine clinical work, but nobody has run the study that would tell a healthy person what to expect, when, or how much. Dose in the morning, change one variable at a time, and use the off days as the comparison.
Feeling Something? Check Here
Do not use Semax at all if any of these apply: pregnancy or breastfeeding · under 18 · diagnosed bipolar disorder, psychosis or an acute anxiety disorder, since Semax is activating and has no human safety data outside supervised hospital use · a seizure disorder · known allergy to the peptide or to the benzyl alcohol in bacteriostatic water · drug-tested athletes, since a 2026 peptide review lists Semax as prohibited by WADA under class S2.
Never use Semax to self-treat a suspected stroke or head injury. That is an emergency room situation, not a vial.
FAQ
Is Semax FDA approved?+
No. A DailyMed search for Semax returns zero drug package labels, and a ClinicalTrials.gov API query returns totalCount 0: not a single registered trial anywhere in the world. It is a licensed drug in Russia, indicated for stroke and neurological disease, and unapproved everywhere else. Every number on this page comes either from Russian-language clinical literature or from convention, and it is worth being clear about which is which.
Should I inject this or use it as a nasal spray?+
Intranasal, if you are going by evidence. Both peptide reviews that cover Semax describe intranasal nasal drops (a 0.1% solution) and IV infusion as the routes used in clinical trials. Subcutaneous injection is not mentioned in any human trial we could find. The vial you buy is lyophilised powder, so it can be reconstituted and drawn into a syringe, but drawing 6 units does not make the subcutaneous route evidence-based; it just makes it measurable. Some people reconstitute and dose the same solution intranasally instead, which at least matches the route the trials used.
What is Semax's half-life?+
Nobody has published one in humans. The closest primary data is a rat study of intranasal Semax at 50 mcg/kg, which found the peptide in brain tissue 2 minutes after dosing and reported rapid enzymatic degradation, with the tripeptide fragment Pro-Gly-Pro dominating the samples. A separate rat study measured a half-life over 1 hour in the presence of isolated brain plasma membranes, which is a benchtop incubation number and not a circulating half-life. Anyone quoting you a precise half-life in minutes for humans is repeating something that was never measured.
Trials used 6 to 18 mg a day. Why does this page suggest 300 mcg?+
Because the routes and the patients are completely different. The acute-stroke study of 30 patients found 12 mg/day most effective for moderate strokes and 18 mg/day for severe ones, given for 5 to 10 days to hospitalised people in the acute phase. A 2018 study used 6 mg/day in 110 post-stroke rehabilitation patients. Those were intranasal or IV doses, in people with an active brain injury, under supervision. The 200 to 600 mcg figures used for daily cognitive purposes are community convention with no trial behind them, and there is no dose-response study in healthy people to bridge the gap.
Will Semax show up on a drug test?+
A 2026 peptide review lists Semax as prohibited by WADA under class S2, peptides acting on the hormonal axis. If you compete in any tested sport, treat it as disqualifying regardless of dose or route, and check the current Prohibited List yourself before you touch it.
Does Semax raise cortisol the way ACTH does?+
It is a heptapeptide, Met-Glu-His-Phe-Pro-Gly-Pro, the ACTH(4-7) fragment with a Pro-Gly-Pro tail added to slow degradation. You will also see it described as an ACTH(4-10) analogue, which is looser but common. The widely repeated claim that this modification strips out the hormonal, cortisol-raising activity of ACTH is plausible and may well be true, but we could not confirm it in a primary source we were able to open. Treat it as unverified rather than established, and do not assume it is inert on the HPA axis just because a vendor page says so.
How long should a course run?+
The published courses were short: 10 days, sometimes repeated after a 20-day gap. There is no published data on continuous or long-term use in anyone, healthy or otherwise. Sticking to 2 to 4 week blocks with a real break is a reasonable extrapolation from how it was actually studied, not a finding.
What side effects have actually been reported?+
Mild ones. A 2026 peptide review describes Semax as not showing significant toxicity at the doses used, with rare adverse events limited to mild nasal irritation from intranasal dosing and transient agitation. That is reassuring as far as it goes, but it reflects supervised medical use of a nasal formulation in Russia. It says nothing about injecting a research-grade reconstituted vial, and there is no systematic Western safety surveillance for this compound at all.
How many units of a U-100 syringe is 300 mcg of Semax?+
Six units, if you mixed a 10 mg vial with 2 mL of bacteriostatic water. That gives 5,000 mcg/mL, and one unit on a U-100 syringe is 0.01 mL, so one unit equals 50 mcg. On that same mix, 200 mcg is 4 units and 600 mcg is 12 units. Change either the vial size or the water volume and every one of those numbers changes: a 5 mg vial in the same 2 mL makes each unit 25 mcg, so 300 mcg becomes 12 units, not 6. Always recalculate from the vial in front of you rather than reusing a unit count you read somewhere.
Sources
Semax has real human data, but all of it is Russian hospital work on intranasal or IV dosing in stroke and cerebrovascular disease. There is no FDA label, no registered trial anywhere in the world, no published human pharmacokinetics, and no human study of the subcutaneous route these vials are actually sold for.
- ·Kinetics of Semax penetration into the brain and blood of rats after intranasal administration. PMID 16523722: rat PK at 50 mcg/kg intranasal; peptide detected in brain tissue at 2 minutes, rapid enzymatic degradation with Pro-Gly-Pro dominating the samples.
- ·Effectiveness of semax in the acute period of hemispheric ischemic stroke. PMID 11517472: 30 patients; most effective daily doses reported as 12 mg for moderate and 18 mg for severe stroke, given for 5 to 10 days.
- ·Efficacy of semax in patients at different stages of ischemic stroke. PMID 29798983: 110 patients; 6,000 mcg/day in two 10-day courses separated by a 20-day interval; plasma BDNF rose.
- ·Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions. PMC13164565: intranasal 0.1% nasal drops; approved as a drug in Russia only; listed as WADA-prohibited under class S2; adverse events limited to mild nasal irritation and transient agitation.
- ·Therapeutic peptides in gerontology. PMC13095733: sequence Met-Glu-His-Phe-Pro-Gly-Pro; intranasal and IV routes in clinical trials; the 6,000 mcg/day regimen; not approved in the West, independent validation lacking.
- ·ClinicalTrials.gov API v2 query for Semax returns totalCount 0. No registered studies anywhere in the world.
- ·DailyMed search for Semax: 0 results. No FDA drug package label exists for this compound.
- ·Binding of Semax to rat forebrain plasma membranes and its biodegradation. PMID 15344653: half-life over 1 hour in the presence of isolated plasma membranes, which is a benchtop figure rather than a circulating half-life.
- ·Mitigating Traumatic Brain Injury. PMC11314487 states plainly that there is no human data on the use of semax in TBI patients.
- ·Semax, an ACTH(4-10) analogue with nootropic properties. PMID 16362768: rat, 0.15 mg/kg intraperitoneal; striatal 5-HIAA rose to 180% over 1 to 4 hours.
The longer treatment of all of this (mechanism, the intranasal-versus-injection question, stacking and vendor testing) lives in the full Semax dosing guide.
Disclaimer: This content is for informational and research purposes only and is not medical advice. Semax is a licensed medicine in Russia for stroke and neurological disease and is unapproved everywhere else: a DailyMed search returns no label, and a ClinicalTrials.gov query returns no registered studies. The microgram doses described here are research-community convention rather than trial-derived figures. Always consult a qualified healthcare professional before starting any peptide protocol. PeptideDeck is not responsible for individual use.