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Cognitive & neuroLimited humanResearch only

Semax

ACTH 4-10 analogue

A Russian-developed neuropeptide used clinically there for stroke and cognition, with limited Western data.

Class

Synthetic ACTH(4-10) analogue / neuropeptide

Half-life

Short (minutes); effects outlast plasma levels

Evidence

Limited human data

Limited human data

Small open-label studies, case series, or trials in a narrow population. Directionally informative, not conclusive.

Overview

Semax is a synthetic analogue of a fragment of ACTH, modified so it retains neuroactive effects without ACTH's hormonal (cortisol-raising) activity. It has been an approved drug in Russia for decades, used for stroke recovery, cognitive disorders, and optic nerve conditions, and is typically given as a nasal spray.

Its proposed mechanism centres on raising BDNF (brain-derived neurotrophic factor) and modulating the dopaminergic and serotonergic systems, which would fit its reported effects on focus, memory, and mood. Russian clinical studies report benefit in ischemic stroke and cognitive impairment.

The evidence problem is access and rigor: most trials are Russian-language, older, and not replicated to Western regulatory standards. It is not FDA approved, and Western controlled data is sparse. Users report nootropic effects, but the high-quality evidence base is thin.

How it works

  • Increases BDNF and NGF expression in the brain, supporting neuroplasticity.
  • Modulates dopaminergic and serotonergic neurotransmission.
  • Neuroprotective and antioxidant effects in ischemia models.
  • Lacks the corticotropic (cortisol-raising) activity of the parent ACTH fragment.

What the research shows

Researched effects

  • Reported improvement in ischemic stroke recovery in Russian clinical use
  • Reported cognitive and attention benefits
  • Neuroprotective effects in animal ischemia models
  • Anecdotal Western reports of improved focus and mental stamina

Limitations & what it won't do

  • Western controlled trials are largely absent; most data is older Russian literature.
  • Not FDA approved.
  • Intranasal bioavailability and optimal dosing are not well standardised.

Dosing protocols

These ranges reflect published trials and community protocols. They are reference information, not a prescription. Doses are per injection unless noted.

Intranasal nootropic protocol (community)

300–600 mcg (0.1% or 1% solution)
Frequency1–3× daily
RouteIntranasal spray
TimingMorning and midday; avoid late dosing if it disrupts sleep
Cycle2–4 weeks, then a break

Concentration matters — a 1% ('Semax 1%') spray delivers roughly 10× a 0.1% spray per drop. Confirm concentration before dosing.

Administration

Not an injectable reconstitution compound

Semax is typically taken intranasal spray, so it doesn't use the vial-and-bacteriostatic-water reconstitution workflow. See the dosing protocols above for how it is taken.

Side effects

Common

  • Nasal irritation
  • Mild headache
  • Occasional overstimulation or insomnia if dosed late

Serious / rare

  • Poorly characterised in Western literature

Contraindications & interactions

Do not use if you have

  • Pregnant, breastfeeding, or trying to conceive

    No pregnancy safety data.

Use caution if you have

  • Mood or psychiatric condition

    Neurotransmitter-modulating peptides can affect mood conditions unpredictably — discuss with a prescriber, especially with bipolar disorder.

  • Seizure disorder

    CNS-active compounds warrant caution with a seizure history.

Medication interactions

  • cautionSSRIs / SNRIsSerotonergic modulation on top of an SSRI/SNRI is unstudied — theoretical additive effect.
  • cautionMAO inhibitorsCombining neuromodulators with MAOIs is a poorly characterised risk.
  • monitorStimulantsAdditive stimulation possible.

What to monitor

  • Mood and sleep
  • Subjective cognitive response

Commonly combined with

References

Research & educational information only — not medical advice.

You must be 18 or older to use this site. The peptides described are presented as research chemicals intended for research purposes only. Most are not approved by the FDA for human use. Dosing ranges reflect what has appeared in the scientific literature or community protocols and are not prescriptions. Nothing here replaces evaluation by a licensed physician who knows your full medical history.

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