Scientific context only. Not medical advice, not a recommendation to use.
At a glance
Synthetic heptapeptide derived from the N-terminal fragment of adrenocorticotropic hormone (ACTH 4-10). Approved in Russia for ischaemic stroke, cognitive function and ADHD in children. Western phase-3 trials absent.
Researched for
Ischaemic stroke (acute and rehabilitation)Cognitive functionADHD (Russian approval)
Official status
US: Unapproved
No FDA approval. Sale as 'research chemical' is not legally covered.
Semax is a tetracosactide fragment analog without hormonal activity at MC2R. Proposed mechanisms include elevation of BDNF and NGF in hippocampus and striatum (in animal models), modulation of dopamine metabolism, and neuroprotective effects via anti-apoptotic pathways. A clear primary receptor is not established.
02
Evidence at a glance
Reading note. The distribution shows on which evidence tier each observation sits. Strong colours mark stronger evidence — weaker tiers are deliberately visible, not hidden.
3 observations · 2 tiers
Human trial
2
Animal model
1
03
What the studies show
Human trial
Mensch
Gusev EI. et al. 2005
Improvement of neurological function in acute stroke treatment versus placebo reported in Russian studies
What does NOT follow: Studies exclusively from Russian centres; Western replication absent; methodological quality discussed controversially.
Animal model
Ratte
Increase of BDNF in the hippocampus in rats after intranasal administration documented
What does NOT follow: Mechanistic marker; clinical relevance in humans not established by robust studies.
Human trial
Mensch
Change in attention and reaction performance in small pilot studies in healthy volunteers reported
What does NOT follow: Participant numbers very small (<30); no replication in phase-3 trials.
05
Pharmacokinetics
Theoretical concentration curve at a half-life of 0.3 h. Pure pharmacokinetic model — not a dosing recommendation.
Which routes of administration the available studies describe — neutral reporting, not a usage guide.
Intranasal
Exclusively intranasal as drop formulation in Russian studies.
07
Known adverse events from studies
Factual reporting of what studies observed. Not a safety statement for individual use.
Human trial
Local irritation of the nasal mucosa
From Russian data; Western systematic pharmacovigilance absent.
gelegentlich
07b
Interactions & combinations
Documented interactions and contraindications from studies, prescribing information and guidelines. Where no data exists, this is stated.
Reporting of risks, NOT a combination guide. The absence of an entry does not mean „safe to combine“ but „not sufficiently studied“.
No documented interactions recorded
We have not yet found robustly documented interactions for this peptide. This does NOT mean none exist — the data is limited.
10
Anecdotal observations
Weakest evidence tier — not supported by studies
Reading note. This section gathers popular claims from communities and forums. They are explicitly marked as weakest-tier evidence. Unblinded self-reports are particularly prone to placebo, recall and confirmation biases.
Why no amounts or protocols are listed here. We deliberately show only WHAT communities report — not in what amount or how it is used. Anecdotal "doses" or "biohacker protocols" are neither verified nor standardised nor safe; publishing them would be a usage guide, which we do not provide on principle. Specific amounts belong in a conversation with a doctor, not in a forum.
In nootropic communities Semax is described as cognitively activating with a dopaminergic component.
common in English-language nootropic forums
Not supported by studies: This claim rests on self-reports and animal-model mechanism findings, not large controlled human trials.
11
Legal status by country
Country
Status
Note
Checked
RU
Prescription
Approved in Russia in two concentrations (0.1% general, 1% for stroke) as intranasal solution.
2026-05-22
United States
Unapproved
No FDA approval. Sale as 'research chemical' is not legally covered.
2026-05-22
Germany
Unapproved
No EMA approval. Not marketable in Germany.
2026-05-22
12
Reconstitution calculator
Pure mg/mL maths — works like a calculator. Not a usage recommendation.
Peptides ship as a dry powder. Once dissolved in a liquid (reconstitution), this calculator answers a single question: how much substance is in one millilitre of solution afterwards?
1Enter the vial's substance amount (printed on the label).
2Enter how much solvent you add.
3Result = concentration in mg per mL.
Printed on the label
/
Liquid you add
=
2.50
mg / mL
5 mg in 2 mL gives 2.50 mg/mL — each millilitre contains 2.50 mg of substance.