Selank side effects and results in studies
The Selank abstracts give no adverse-event rates; the one tolerability finding is from a 70-patient Russian trial, where adding Selank to phenazepam reduced phenazepam's own side effects on the UKU scale. The measured outcomes are anxiety scale scores, quality of life, serum enkephalin and cytokines in small Russian trials, and behaviour, BDNF and tissue changes in mice and rats.
Adverse events reported
| Event | As reported | Source |
|---|---|---|
| Side effects of phenazepam when combined with Selank | Attention and memory impairment, asthenia, sedation, longer sleep, sexual disturbances, emotional indifference and orthostatism were reduced with Selank added, during treatment and after withdrawal (UKU scale, n=70). Selank's own adverse-event rate not stated in the abstract | Medvedev VE et al. |
| Side effects, general statement | The abstract describes Selank as not causing the side effects typical of most anxiolytics; no rates or data given | PMID 11550013 |
| Evidence base | A 2021 US review describes Selank as a poorly studied Russian drug with a GABAergic mechanism | PMID 34396551 |
Outcomes measured
| Outcome | Result as reported | Source |
|---|---|---|
| Anxiety scores versus medazepam (GAD, neurasthenia) | Similar anxiolytic effect, with added anti-asthenic and psychostimulant effects | Zozulia AA et al. |
| Serum leu-enkephalin half-life | Low in GAD and neurasthenia; increased during Selank treatment, mostly in GAD | Zozulia AA et al. |
| Onset of phenazepam effect on HDRS | Earlier when Selank was added | Medvedev VE et al. |
| Quality of life (SF-36) | Improved with Selank added to phenazepam | Medvedev VE et al. |
| Duration of anxiolytic effect | Lasted a week after the last Selank dose (n=60) | Medvedev VE et al. |
| Serum Th1/Th2 cytokine balance | Changed after 14 days of Selank in GAD and neurasthenia | Uchakina ON et al. |
| Morphine withdrawal index in rats | Reduced by 39.6% after a single 0.3 mg/kg injection | Konstantinopolsky MA et al. |
| Memory after chronic ethanol in rats | Ethanol-induced memory and attention disturbances prevented; hippocampal and frontal BDNF rise prevented | Kolik LG et al. |
| Liver morphology in rats under chronic foot-shock stress | Stress-induced degenerative changes reduced at all doses; largest effect at 300 μg/kg | PMID 31243679 |
| Influenza A (H3N2) in cell culture and mice | Viral reproduction suppressed in cells given Selank 24 h before infection; highest survival in mice on the preventive scheme | PMID 19882898 |
What the studies don't show
No abstract here gives an adverse-event rate for Selank itself, so its safety profile in people is not established by these records. The reported benefits come from small Russian trials whose abstracts leave out dose and route, and from rodent and cell models. There are no long-term human data.