Selank is a synthetic seven-amino-acid peptide built around tuftsin, developed at the Russian Academy of Sciences as an anxiolytic and nootropic. It is approved as a medicine in Russia but not in the UK, US, EU, Australia or Canada, and almost all of its supporting research, including the published anxiety trials, has been produced by Russian groups and not independently replicated in the West.
Semax is a synthetic seven-amino-acid peptide modelled on a fragment of ACTH(4-10). It is approved as a medicine in Russia as a nootropic and an add-on to ischaemic stroke recovery, with positive trials from Russian groups. It is not approved in the UK, US, EU, Australia or Canada, where it is sold only as a research chemical.
Both peptides share an evidence grade of C. The right choice depends less on the data and more on what you're trying to do, Selank for generalised anxiety, Semax for ischaemic stroke recovery.
Approved in Russia as a prescription anxiolytic. Russian comparative trials (e.g. Medvedev et al., Zh Nevrol Psikhiatr Korsakova 2014/2015) report efficacy in the same range as phenazepam with fewer sedative side effects. No regulator outside Russia has reviewed or endorsed this use.
Animal work (Kozlovskaya et al., Behav Neurol 2017) reports that Selank enhances the anxiety-reducing effect of diazepam in chronic-stress models. Suggests a real GABAergic interaction; not a substitute for human trial evidence.
As a tuftsin analogue, Selank modulates cytokine and chemokine gene expression in rodent and cell-culture models (Kolomin et al., Mol Immunol 2014). Mechanistically interesting; no clinical immunology endpoint has been demonstrated in humans.
Registered in Russia as an adjunct to ischaemic stroke treatment and rehabilitation. A 2018 Russian trial in 110 post-stroke patients reported faster Barthel-index recovery and elevated plasma BDNF with Semax courses. Not approved or routinely used in Western stroke care.
Registered Russian indication for "mental and emotional stress" and attention/memory support. Underlying data is mostly Russian preclinical work plus small open-label studies.
Used in Russian paediatric practice for attention disorders. Published rationale rests on Semax's effects on dopamine and BDNF (Tsai, Med Hypotheses, 2007). No Western RCTs in ADHD.
In the published Russian trials, Selank has a reasonably clean short-term safety profile, fewer sedative, cognitive and dependence-type adverse effects than the benzodiazepine comparator phenazepam. Those trials were small, conducted by the developers, and have not been independently replicated, so the safety signal is weaker than it appears at first glance. Long-term safety in humans outside the original cohorts is essentially unknown. Products sold in Western markets as "Selank" are unregulated research chemicals, purity, sterility and dose-by-dose consistency are not guaranteed, and intranasal use of an unregulated peptide carries its own contamination risk. People who are pregnant, breastfeeding, immunocompromised, or taking other medicines, particularly benzodiazepines or other GABAergic agents, should be especially cautious.
In the Russian clinical record, Semax has a generally favourable short-term safety profile, most reported adverse events are mild and local (nasal irritation, transient mucosal effects) and the molecule is non-hormonal despite its ACTH origin. The qualifier is the same one that applies to its efficacy data: most of the safety evidence comes from the developing groups, and the long-term and large-population Western safety record simply does not exist. Theoretical concerns include unknown effects of chronic BDNF/dopaminergic modulation, interactions with psychiatric and stimulant medications, and the fact that research-chemical Semax sold online is not quality-controlled, purity, sterility and dose accuracy vary. People who are pregnant, breastfeeding, have psychiatric conditions, take other CNS-active drugs, or are immunocompromised should be especially cautious.
Both peptides share an evidence grade of C. The right choice depends less on the data and more on what you're trying to do, Selank for generalised anxiety, Semax for ischaemic stroke recovery.
Pepwyse comparison pages are generated from the same structured data behind each peptide profile. Want a different head-to-head? Use the compare picker or ask Selank directly via the Ask-Peppy button. Not medical advice, see how we grade evidence.