Semax is a seven-amino-acid peptide made from a fragment of the hormone ACTH, developed in Moscow and registered in Russia as nasal drops. Online, it is sold as a research peptide for focus and memory, and a steady share of searches ask whether it treats ADHD.
This page counts what the published and registered record actually holds on that question, with the search strings printed so anyone can repeat them. The side-effect record is on our semax side effects page; the figures used in the Russian studies are on our semax dosage page; the wider class is on cognitive peptides. Peptide Lexicon's semax entry explains the molecule. Nothing here is advice on treating ADHD, which is a diagnosis and a treatment decision for a clinician.
The census
Searches run on 28 October 2026:
| Source | Query | Records | Trials in ADHD |
|---|---|---|---|
| PubMed | semax |
234 | — |
| PubMed | semax AND (ADHD OR attention deficit OR hyperactivity) |
5 | 0 |
| PubMed | semax AND (child OR children OR pediatric OR paediatric) |
5 | 0 |
| PubMed | semax AND (clinical trial[pt] OR randomized controlled trial[pt]) |
4 | 0 |
| ClinicalTrials.gov | intervention: semax | 0 | 0 |
| ClinicalTrials.gov | semax AND ADHD | 0 | 0 |
The five ADHD-related records are:
- Tsai, Medical Hypotheses, 2007 — a hypothesis paper. It argued that semax "may have good therapeutic potential in ADHD" because rodent work showed it stimulates brain-derived neurotrophic factor (BDNF) and "can augment the effects of psychostimulants on central dopamine release". It reported no new data. doi:10.1016/j.mehy.2006.07.017
- Maslova et al., 2002 and 3. Maslova et al., 2003 — the same Moscow group's rat studies (one in Russian, one its English translation), indexed to semax as part of a "peptide constellation": hypoxia before or after birth produced hyperactivity and poorer learning "typical for the attention deficit syndrome", and a "peptide constellation" given afterwards reduced most of the behavioural changes. These are animal models of brain injury, not ADHD in people.
- Inozemtseva et al., 2024 — a rat chronic-stress study of semax and melanotan II; it matches the search because its abstract discusses hyperactivity of the stress-hormone (HPA) axis, not attention.
- Lapochkin et al., 2026 — the expert-council resolution described below.
The four records PubMed tags as clinical trials of semax are in ischaemic stroke (Gusev, 1997 and 2018), motor neuron disease (Serdiuk, 2007) and optic nerve disease (Polunin, 2000). None enrolled children, and none measured attention as a condition.
The two paediatric references FDA found
PubMed's search does not reach everything. FDA's 2026 compounding review, which searched more widely, listed every reference in which a person received semax, and two were in children (our semax side-effects page sets out the full table): Aminova 2016, 331 children with tics and Tourette syndrome, given semax with another nootropic and neuroleptics; and Proskurina 2018, 120 adolescents aged 12–14 with depression, given 0.1% semax with cognitive behavioural therapy and physiotherapy. Both were meeting abstracts without full reports, in both semax was one of several treatments given at once, and neither discussed adverse events. The Aminova abstract, in a neighbouring childhood neurological condition, is the closest thing in the record to the question on this page — and it is still not a study of ADHD, and cannot separate semax from the drugs given with it.
The 2026 Russian rating
On 16 July 2026 an expert council convened by Russia's National Association of Pediatric Neurologists reviewed adjunct drugs used in Russian practice for hyperkinetic disorders (ICD-10 F90, ADHD) in children and adolescents. Its resolution, published in Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova (doi:10.17116/jnevro2026126092126), split them by evidence:
- Group A — strongest evidence, defined as a double-blind randomised trial in ADHD that met its primary endpoint: one product, Prospekta.
- Group B — "limited evidence base": Cortexin, Tenoten for children, Cerebrolysin, Semax, Cogitum, Magne B6, Pantogam and Mexidol.
The council added that adjunct drugs are to be used only inside a multidisciplinary approach with psychoeducation and behavioural interventions, and that they do not replace atomoxetine where it can be prescribed. That is the most favourable published body on semax's own home ground, and it places semax below the evidence bar of a single positive controlled trial. The abstract does not list which semax studies the council weighed; we could not open the full Russian text from here, and do not describe it further.
Why the animal mechanism is not an answer
The case made in 2007 rests on two observations from rodents: semax raises BDNF in the brain, and it can amplify dopamine release when combined with a stimulant. Both are real findings in animal work, and both are also true of many substances that have never become ADHD treatments. A mechanism suggests a trial; it does not substitute for one. Nineteen years after the hypothesis was published, the trial it called for does not appear in PubMed or in the international registry.
Semax's own dosing literature makes the gap wider. The dose-stating human records on our dosage page describe a 0.1% or 1% nasal solution in adults — after retinal surgery, in healthy volunteers, in psoriasis; the two paediatric abstracts above describe a 0.1% solution or give no strength, and neither isolates semax's effect.
The safety side of the question
FDA reviewed semax in 2026 as a candidate bulk substance for compounding. Its briefing for the July 2026 advisory committee found eight usable human references, only one of which reported on adverse events, and no study by subcutaneous injection — the details are on our semax side effects page. The two paediatric references it lists did not discuss adverse events. Products sold online as research semax carry no label, no paediatric data and no quality record; our guide to reading a certificate of analysis explains what a seller's document can and cannot show.
What is not established
- Any effect of semax on ADHD symptoms in people — no randomised, open-label or case-series study in a diagnosed population was found.
- Paediatric safety: the two paediatric abstracts FDA found say nothing about adverse events.
- How semax compares with approved ADHD medicines — no comparison exists.
- Which Russian clinical experience the 2026 council relied on: the published abstract does not name it.
Questions about attention, focus or an ADHD diagnosis, in a child or an adult, belong with a clinician who can assess them. How semax compares with two other compounds sold for focus is on our Adamax vs Semax and Dihexa vs Semax pages.
Sources and dates
- PubMed E-utilities searches as printed above, run 28 October 2026; abstracts of PMIDs 16996699, 14552554, 11938648, 39442746, 42910684, 29798983, 18379501, 10741256 and 11517472 read the same day.
- ClinicalTrials.gov API v2, intervention "semax" and term "semax AND ADHD" — 0 studies each, queried 28 October 2026.
- Tsai SJ. Semax, an analogue of adrenocorticotropin (4-10), is a potential agent for the treatment of attention-deficit hyperactivity disorder and Rett syndrome. Med Hypotheses 2007;68(5):1144–6.
- Lapochkin OL et al. Expert Council resolution: adjunctive pharmacotherapy for hyperkinetic disorders (ADHD) in children and adolescents. Zh Nevrol Psikhiatr Im S S Korsakova 2026;126(9 Vyp 2):126–135 (abstract read 28 October 2026).
- FDA briefing document, semax-related bulk drug substances, Pharmacy Compounding Advisory Committee, July 2026 — as summarised on our semax side-effects page (read 27 September 2026).