Editorial stack guide · Cognition
Cognition: Semax, Selank, nootropic-adjacent
Oliver Mackman · Editorial director · Best Business Loans Ltd (16833937)
Last updated 2026-05-22
Editorial with affiliate links. We earn from purchases via outbound retailer / clinic links. How we are funded.
AI-friendly summary · Cognition stack
Semax and Selank are two Russian-research nootropic peptides developed at the Institute of Molecular Genetics in Moscow. Both are registered pharmaceuticals in the Russian Federation but have no UK marketing authorisation. The wider nootropic-adjacent landscape includes additional compounds with varying regulatory status. The literature is heavily concentrated in specific clinical populations rather than cognitive enhancement in healthy adults. PeptideClear publishes encyclopedia commentary only. We do not recommend specific stacks for specific people. A combination of peptides should be discussed with a UK-registered prescriber.
Compounds in the cognitive-research conversation
Two Russian-research peptides sit at the centre of the peptide-side cognitive conversation, with a wider nootropic-adjacent landscape around them. Each carries a distinct mechanism, evidence base and UK regulatory position.
Semax
Evidence: Mixed evidenceSemax is a synthetic heptapeptide derived from the ACTH 4-10 fragment with a modified C-terminus (Pro-Gly-Pro). Developed at the Institute of Molecular Genetics in Moscow. Registered in the Russian Federation for acute ischaemic stroke and other neurological indications. The literature describes modulation of BDNF and NGF expression in rodent brain tissue and a range of effects on attention, memory and recovery endpoints in clinical samples. Western independent replication is sparse.
Encyclopedia entry for Semax ·Selank
Evidence: Mixed evidenceSelank is a synthetic tuftsin-derived heptapeptide also developed at the Institute of Molecular Genetics in Moscow. Registered in the Russian Federation for generalised anxiety disorder. The literature describes modulation of enkephalin-degrading enzyme activity and GABA-system signalling. Russian clinical-trial work reports anxiolytic effects comparable to benzodiazepine reference drugs without the sedation and dependency profile. The Russian clinical literature also describes downstream effects on attention and working memory under stress.
Encyclopedia entry for Selank ·Nootropic-adjacent compounds
Evidence: MechanisticThe wider nootropic landscape includes Cerebrolysin (a porcine-brain-derived peptide preparation registered in some non-UK markets for neurological recovery), Noopept (a synthetic dipeptide developed in Russia), and a range of non-peptide compounds (the racetam family, modafinil, methylphenidate). Each sits in a different regulatory category. Some are POM in the UK. Some are not approved at all. The evidence base varies sharply across the group.
What the literature shows
The Semax literature originates from the Myasoedov, Andreeva and Asmarin research groups at the Institute of Molecular Genetics in Moscow and the M.V. Lomonosov Moscow State University. Russian clinical work in acute ischaemic stroke reports improved functional recovery scores in the published trial samples. Mechanistic work in rodents describes upregulation of BDNF and NGF expression in hippocampal and cortical tissue. The translation of these findings to cognitive enhancement in healthy adults is not the population the trials were designed to assess.
Selank research follows a parallel pattern. The published Russian clinical literature is anchored on generalised anxiety disorder, with reports of anxiolytic efficacy comparable to benzodiazepine reference drugs. Mechanistic work describes modulation of enkephalin-degrading enzyme activity, leading to extended action of endogenous enkephalins, and effects on GABA-system signalling. Cognitive endpoints in the published clinical literature sit as secondary measures rather than primary endpoints, typically describing attention or working memory performance under stress conditions in clinical samples.
The nootropic-adjacent literature is heterogeneous. Cerebrolysin has a longer clinical research history in Europe and Asia, with trial work in vascular dementia and stroke recovery. Noopept research originates largely from Russian groups and remains poorly characterised in independent Western trials. Non-peptide cognitive enhancers (modafinil, methylphenidate) have substantial clinical trial bases for their licensed indications, with off-label cognitive enhancement use being a separate research and regulatory question.
What we do not know
- · Whether Semax or Selank produces measurable cognitive improvement in healthy adults without an underlying clinical indication.
- · Whether the Russian clinical findings replicate in independent Western trials at the scale needed to settle the headline claims.
- · Whether nasal-spray administration achieves the central-nervous-system concentrations assumed by the proposed mechanism of action.
- · Whether combining Semax and Selank produces additive, synergistic or null effect versus either alone in any controlled trial endpoint.
- · Long-term safety of either compound in healthy adults at any dose or duration.
- · Whether observed effects reflect peptide pharmacology, placebo response, or both, in the trial designs used in the originating Russian literature.
- · The cognitive-enhancement signal-to-noise ratio across the wider nootropic-adjacent landscape, which remains contested across reviewers.
UK regulatory framing
Semax
Not a controlled drug under the Misuse of Drugs Act 1971. Not scheduled under the Psychoactive Substances Act 2016. No UK marketing authorisation as a medicine. Sold by UK research peptide retailers under research-use-only framing. Russian Federation registration does not create a UK licensing route.
Selank
Same UK position as Semax. No MoDA or PSA listing. No MHRA marketing authorisation. Russian registration for generalised anxiety disorder does not extend to UK licensing. Sold by UK research peptide retailers under research-use-only framing.
Nootropic-adjacent compounds
Status varies. Cerebrolysin is not licensed in the UK. Noopept is not licensed in the UK. Modafinil is POM in the UK (licensed for narcolepsy). Methylphenidate is POM (licensed for ADHD) and additionally a controlled drug under the Misuse of Drugs Act (Schedule 2). Always verify the specific regulatory status of any compound before assuming it sits in the same category as Semax and Selank.
How a UK practitioner would discuss this
A UK GP, neurologist or psychiatrist approaching the cognition conversation will typically begin by separating clinical questions from cognitive-enhancement curiosity. Clinical presentations (memory complaints, attention difficulties, anxiety affecting concentration, post-stroke cognitive change) sit within established assessment and treatment pathways with UK-licensed pharmacological and non-pharmacological options where indicated. Cognitive enhancement in healthy adults sits in a separate research and ethical conversation that NHS pathways do not formally address.
Research peptides occupy a third position. A UK-registered prescriber discussing Semax or Selank would frame them as Russian-registered pharmaceuticals without UK marketing authorisation, with research literature that does not address cognitive enhancement in healthy adults as a primary endpoint, and without integration into UK clinical pathways. The discussion would typically include the practical reality that no UK clinic or pharmacy supplies them in any licensed context.
The wider nootropic-adjacent conversation requires sharper regulatory care because some compounds in that landscape are POM (modafinil, methylphenidate) and prescribing them outside their licensed indications carries professional and legal weight that does not apply to unlicensed research compounds. A UK-registered prescriber is the appropriate person to navigate that landscape.
Where to learn more
- · Encyclopedia entry: Semax
- · Encyclopedia entry: Selank
- · Glossary: peptide and nootropic terminology
- · Research peptides hub: all UK research peptide entries
- · Stacks hub: all editorial stack guides
Frequently asked questions
Are Semax and Selank legal in the UK?
Why nasal spray administration?
Do nootropic peptides actually improve cognition in healthy adults?
What about other nootropic-adjacent compounds?
Who should I speak to before considering these?
PeptideClear publishes encyclopedia commentary only. We do not recommend specific stacks for specific people. A combination of peptides should be discussed with a UK-registered prescriber. Semax and Selank are sold under research-use-only framing. Nootropic-adjacent compounds vary in UK regulatory status from food supplement to Schedule 2 controlled drug.
Read our full methodology and how we are funded.
Ready to buy
Shop UK peptides, collagen and GLP-1 routes
Compare UK retailers, clinics and pharmacies across every PeptideClear category.