Selank

Semax's sibling — a Russian anxiolytic peptide nasal spray, marketed there for anxiety with claimed benzo-like calm minus sedation or dependence. Popular in the same circles for the same reason: an anti-anxiety agent that is not a controlled substance.

Selank is a synthetic version of tuftsin, a naturally occurring immune-signalling peptide, modified to last longer in the body. Its claimed effect is anxiolytic — reducing anxiety — through modulation of GABA signalling and of the enkephalin system, without the sedation, dependence or cognitive dulling that define benzodiazepines. That "benzodiazepine effect without benzodiazepine problems" framing is precisely what makes it attractive and precisely what has never been established in a trial anyone outside its country of origin has been able to check.

Same shape as Semax: Russian trials report anxiolytic effects comparable to benzodiazepines in generalized anxiety, with the same auditability problem. Animal mechanism work (GABA modulation, enkephalin degradation) is real but thin. Western replication: none of note.

• Approved in Russia as an anxiolytic. Not approved anywhere in the West.
• The clinical literature is small, Russian-language and largely from the research group that developed it. It has not been independently replicated.
• No Western randomised controlled trial exists.
• Reported effects on anxiety scales are LIMITED at very low certainty — the comparative trials are small, active-controlled rather than placebo-controlled, and unreplicated. For healthy-person benefit: None shown.
• Its tolerability record within that literature is good, but a good safety record in a small unreplicated literature is weak evidence rather than reassurance.

Given intranasally, with a short peptide half-life. Claimed effects are described as lasting longer than blood levels would suggest, which is asserted rather than well characterised. As with the other Russian nootropic peptides, what is sold in the West is research-chemical supply with unverified purity and sterility, not the approved pharmaceutical product.

Reported side effects in the Russian literature are minimal, which should be read as "minimally studied" as much as "safe". Unknown long-term profile, unregulated supply, and the specific risk of treating real anxiety with an unverified agent instead of things with actual evidence.

• Anyone using it instead of treatment for a diagnosed anxiety disorder
• Anyone pregnant or breastfeeding
• Anyone taking benzodiazepines or other sedatives
• Anyone unwilling to accept unverified grey-market product

• No characterised interaction profile in Western literature.
• Benzodiazepines and other sedatives: combination safety data is inadequate. One Russian study deliberately combined it with phenazepam, which proves the combination has been tried, not that it is safe.
• Antidepressants, where the enkephalin and serotonin claims make interaction plausible but unstudied.

• Nasal irritation.
• Whether it is actually working, honestly assessed — anxiolytic effects are unusually susceptible to expectation.
• Whether it is being used in place of treatment for a diagnosed anxiety disorder, which is the real risk with this compound.
• Source and product quality, which is the dominant practical hazard.

Withdrawal and rebound have not been adequately studied — a short presumed half-life is not evidence they cannot occur, and FDA lists important missing human safety information for this peptide, including immunogenicity risk from aggregation and impurities. Anxiety returns to whatever it was; nothing here treats an underlying cause. Anyone who found it genuinely helped with significant anxiety has a reason to see someone about the anxiety, not a reason to keep buying grey-market peptide.

US: not approved, not scheduled — grey-market "research" sales. Prescription product in Russia.

Papers about this compound, not proof of the claims above. A title says what was studied, which is sometimes a negative result or a different question entirely.

• Optimization of the treatment of anxiety disorders with selank
  Zh Nevrol Psikhiatr Im S S Korsakova, 2015
• A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders
  Zh Nevrol Psikhiatr Im S S Korsakova, 2014
• Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia
  Zh Nevrol Psikhiatr Im S S Korsakova, 2008

• Functional Connectomic Approach to Studying Selank and Semax EffectsDokl Biol Sci · 2020
• Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future DirectionsJ Am Acad Orthop Surg Glob Res Rev · 2026
• Selank, a Peptide Analog of Tuftsin, Attenuates Aversive Signs of Morphine Withdrawal in RatsBull Exp Biol Med · 2022
• Effect of Selank on Morphological Parameters of Rat Liver in Chronic Foot-Shock StressBull Exp Biol Med · 2019
• The Influence of Selank on the Level of Cytokines Under the Conditions of "Social" StressCurr Rev Clin Exp Pharmacol · 2021
• Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in RatsBull Exp Biol Med · 2019
• Selank Administration Affects the Expression of Some Genes Involved in GABAergic NeurotransmissionFront Pharmacol · 2016
• GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 CellsFront Pharmacol · 2017
• Peptide Selank Enhances the Effect of Diazepam in Reducing Anxiety in Unpredictable Chronic Mild Stress Conditions in RatsBehav Neurol · 2017
• Selank Inhibits Ethanol-Induced Hyperlocomotion and Manifestation of Behavioral Sensitization in DBA/2 MiceBull Exp Biol Med · 2016
• Effect of Selank on Spontaneous Synaptic Activity of Rat Hippocampal CA1 NeuronsBull Exp Biol Med · 2017
• The temporary dynamics of inflammation-related genes expression under tuftsin analog Selank actionMol Immunol · 2014