Selank: Research, Mechanism, and Clinical Evidence for Anxiety and Cognition

What it is

Tuftsin is a four-amino-acid fragment of an antibody that helps immune cells work. In the 1990s, researchers at the Institute of Molecular Genetics in Moscow attached three more amino acids to it to stop it breaking down, and found the result calmed anxiety in animals. They called it Selank. It is a nasal spray, and in Russia it is a prescription drug for anxiety.

It is the sibling of Semax, from the same institute and the same idea: take a natural peptide fragment, stabilize it, deliver it through the nose. Semax was aimed at attention and stroke recovery; Selank at anxiety.

What it is studied for

Anxiety disorders, in Russian clinical trials. Memory and learning, in rats. Immune effects, in the lab. Nothing has been trialed outside Russia.

What the evidence actually shows

In humans

The clinical work comes from Russian psychiatric hospitals. In patients with generalized anxiety and adjustment disorders, Selank nasal spray reduced anxiety scores about as much as medazepam, a benzodiazepine used as the comparison, and without the sedation, memory impairment, or withdrawal that benzodiazepines cause (Zozulya et al., 2008). Patients with anxiety that came with fatigue and poor concentration reported those improving too.

These were small studies, published in Russian journals, run by the group that developed the drug. No Western group has repeated them, and no large placebo-controlled trial exists. That is the ceiling on what can be claimed. See how peptides are studied.

In animals

Rats given Selank nasally show higher BDNF, a growth signal for neurons, in the hippocampus, the memory center (Inozemtseva et al., 2008). It also changes the activity of genes for GABA-A receptor subunits, the receptors benzodiazepines act on, which fits the anti-anxiety effect (Kasian et al., 2017). Rats on Selank learn and remember better in maze tests and show less anxiety-like behavior.

From user reports

Calm without drowsiness, arriving within 15 to 30 minutes of a nasal dose and lasting a few hours. Some describe clearer thinking, some feel nothing. Nasal irritation is the common complaint. Users often pair it with Semax, an untested combination.

How it works

Three mechanisms have support in the lab. Selank slows the enzymes that break down enkephalins, the body’s own opioid-like calming peptides, so they last longer. It shifts the balance of GABA signaling, the brain’s main inhibitory system, without binding the benzodiazepine site directly. And it raises BDNF. It also nudges serotonin and a wide set of immune-related genes. Which of these matters most in a person is not known.

How it is used in studies

The Russian trials used a 0.15% nasal solution, a few drops per nostril two or three times a day, for two to four weeks. Users follow the same pattern, 250 to 500 micrograms per dose nasally, or inject it under the skin at similar doses, in courses of a few weeks with breaks. Open vials should be refrigerated. See the storage guide.

Side effects and unknowns

Reported in the trials and by users: nasal irritation, occasional headache, rare fatigue. No sedation, no dependence, no withdrawal documented. Nothing is known about long-term use, about interactions with antidepressants or other psychiatric drugs, or about use in pregnancy. Injected Selank has no study behind it at all. See the safety guide.

How it compares

• Semax: the sibling, aimed at focus and memory rather than anxiety; the two are often stacked, with no study of the combination.
• DSIP: studied for deep sleep; a different problem.
• Benzodiazepines: far more evidence, and the sedation, tolerance, and withdrawal Selank’s trials were designed to avoid.
• SSRIs: the standard anxiety treatment, with large trials Selank does not have.

Legal status

Approved in Russia as a prescription nasal spray. Not approved by the FDA or any Western regulator; sold as a research chemical in the United States. Not on the WADA Prohibited List.

Bottom line

Selank has something most peptides on this site lack, human trials showing it does what it claims, and something that limits how much that is worth: they are small, Russian, and unrepeated. If the results hold, it is an anti-anxiety drug without the usual costs. Whether they hold, nobody outside the group that made it has checked.

References

1. Zozulya AA, et al. (2008). The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity. Bull Exp Biol Med. PubMed
2. Inozemtseva LS, et al. (2008). Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus. Dokl Biol Sci. PubMed
3. Kasian A, et al. (2017). Selank administration affects the expression of some genes involved in GABAergic neurotransmission. Front Pharmacol. PubMed

See also

• Peptide
  DSIP (Delta Sleep-Inducing Peptide): Research, Mechanism, and Evidence for Sleep Modulation

  DSIP is a nine-amino-acid peptide your body makes, found in 1977, studied for deepening slow-wave sleep and calming stress hormones. The human studies are small and decades old, and nobody has ever found its receptor.

• Peptide
  Epithalon (Epitalon): Research, Mechanism, and a Careful Look at the Anti-Aging Evidence

  Epithalon is a four-amino-acid peptide from a Russian lab, studied for switching on telomerase and restoring melatonin. It lengthened telomeres in a dish and extended lifespan in mice, and it has never been tested for aging in people.

• Peptide
  KPV: What the Research Shows About This Anti-Inflammatory Tripeptide

  KPV is the last three amino acids of alpha-MSH, a hormone that both tans skin and calms inflammation. The fragment keeps the calming and drops the tanning. It reduced gut and skin inflammation in mice; no human trial exists.