Nootropic
Semax
A synthetic heptapeptide: the ACTH(4-7) fragment extended with a Pro-Gly-Pro tail that blocks rapid enzymatic breakdown.
Also known as ACTH(4-7)-PGP · Met-Glu-His-Phe-Pro-Gly-Pro · N-Acetyl Semax Amidate · NASA
At a glance
Dose summary
No reliable human half-life has been published for Semax, so none is listed rather than guessed at.
No regulator and no trial set these numbers. They describe what people actually do, recorded so you can see the range rather than guess at it — which is not the same thing as a recommendation.
Reconstitution
What to draw, at the usual vial
A 5 mg vial reconstituted with 3 mL of bacteriostatic water gives 1.67 mg/mL. A typical 300 mcg dose is 0.180 mL — pull the plunger to 18 units on a U-100 syringe.
Same dose, other vial sizes
| Vial | Water | Concentration | Draw | Units | Doses |
|---|---|---|---|---|---|
| 5 mg | 3 mL | 1.67 mg/mL | 0.180 mL | 18 units | 16 |
| 10 mg | 3 mL | 3.33 mg/mL | 0.090 mL | 9 units | 33 |
| 30 mg | 3 mL | 10.00 mg/mL | 0.030 mL | 3 units | 100 |
The highlighted row is the one quoted above: the smallest listed vial that holds at least four typical doses. Change any of it — a different vial, more or less water, a different dose — on the reconstitution calculator, which draws the syringe to true U-100 graduations.
Mechanism & evidence
What it is, and what is known
A synthetic heptapeptide: the ACTH(4-7) fragment extended with a Pro-Gly-Pro tail that blocks rapid enzymatic breakdown. It has no ACTH-like hormonal activity. Semax is a registered medicine in Russia and is given intranasally as a 0.1% or 1% solution; it is NOT approved in the US or EU and Western trial data is essentially absent, so the human evidence base is Russian-language and mostly from a small number of groups.
Route matters here: it is an intranasal drug, not an injectable, and the nose-to-brain path is the whole point of the formulation. Russian dosing convention for cognitive and asthenic indications is roughly 200-2000 mcg per day split across two or three administrations (a few drops or sprays per nostril); the per-dose range listed here reflects that split, not the daily total. Much higher doses (around 12 mg/day of the 1% solution) have been used in acute ischaemic stroke under hospital supervision and are outside the scope of self-directed use.
Plasma half-life is measured in minutes, so no meaningful hourly figure is listed; reported CNS effects outlast plasma presence.
The caveat
A registered medicine in Russia; Western trial data is essentially absent and the evidence base is Russian-language work from a small number of groups.Tolerability
Reported side effects
- Nasal stinging, dryness or irritation at the spray site
- Mild headache
- Overstimulation, irritability or restlessness, dose-dependent
- Disturbed sleep if dosed late in the day
Hard stops
Do not use this if
- Pregnancy, possible pregnancy, or breastfeeding
- Under 18
These are flags, not a screening. They do not replace a conversation with a clinician who knows your history.
Handling
Storage
Keep it cold, keep it dark, and label the vial with the date you mixed it. Discard anything cloudy or past the window above.
Combinations
Commonly stacked with
Stacking multiplies the side-effect surface and makes it impossible to tell which compound did what. Add one thing at a time.
Where it shows up
Protocols using this compound
References
Sources
Educational information only, not medical advice. Talk to a licensed clinician before starting, changing, or stopping anything.