Look at the people, not the headline
What did the studies actually test?
Who took part? What was compared? What changed? Those questions matter more than a confident headline.
The short answer
The patient studies are small Russian anxiety studies; the brain-scan study involved healthy people.
Look for the question each study can answer before treating a result as a promise.
Read the human studies with their limits
Patient study summaryAnxiety: a comparison with another medicine.Open the evidence note
In a Russian study published in 2008, 62 people with anxiety received Selank or medazepam, an older calming medicine.
The summary reported similar anxiety relief in the groups; it described no group given a look-alike treatment without the medicine being tested.
A placebo is a look-alike treatment without the medicine being tested.
Without that comparison, this study cannot show that Selank beat no treatment.
The English summary also did not state whether groups were assigned by chance or whether people knew which medicine they received.
Those details matter: differences between the people in each group, or expectations about a medicine, could affect the relief they report.
Read the anxiety study summaryPatient study summaryAnxiety: Selank added to another medicine.Open the evidence note
A Russian study published in 2015 involved 70 people; all received phenazepam, a calming medicine, and 40 also received Selank.
The authors reported earlier relief and fewer unwanted effects of phenazepam with Selank added.
This tests Selank added to another medicine. It does not test Selank alone or compare it with a look-alike treatment lacking the tested medicine.
The English summary does not say how people were assigned to the groups. Differences between the groups could affect the results.
Read the add-on study summaryHealthy-person study summaryBrain scans: changes in healthy people.Open the evidence note
A study published in 2020 scanned the brains of 52 healthy people after Selank, another peptide, or a look-alike treatment without the tested medicine.
A placebo is a look-alike treatment that lacks the tested medicine.
Brain-scan changes in healthy people are not proof of anxiety relief.
Read the brain-scan study summaryAnimal-study recordMemory: the evidence is in rats.Open the evidence note
The cited Selank learning and memory work was done in rats; the human patient studies measured anxiety.
A result in a rat learning test does not establish a memory benefit in people.
Read the rat-study recordThe short answer
As of September 2026, much of the published Selank research comes from a linked group of Moscow institutes.
Results from the same research group leave the question of confirmation by other groups open.
Ask how a study fits your concern
Ask for the study itself when an offer promises more than the study summaries on this page report. Those summaries are a starting point for reading the full paper.