Selank peptide is a synthetic peptide described as an anxiolytic (anti-anxiety) and nootropic (cognitive-enhancing) research compound. It was built from tuftsin, a small natural protein made by the immune system, by Russian research groups. These are the main areas researchers have looked at:
- Anxiety and stress. Researchers have studied whether selank can calm the nervous system and lower anxiety without the heavy sleepiness that comes with traditional anxiety medications called benzodiazepines. In one small trial its anxiety effect was similar to a standard medication, and questions about dependence and withdrawal are still open.
- Focus and memory. It has been explored for focus, concentration, learning, and memory. In the papers reviewed, the signs of this come from small studies and lab work.
- Mood. In lab work, selank has been linked with the monoamine systems, which include serotonin and dopamine, two chemicals involved in mood.
- Immune and brain signaling. Because it comes from an immune peptide, it has also been studied for immune effects. Links to BDNF, a protein that helps brain cells grow, come mostly from work on Semax in the papers reviewed.
This guide explains what selank is, how it is thought to work, what the published papers found, how it differs from Semax, and how it compares with traditional anxiety medications. It describes research only and is not advice for any person. For the sister compound, see the Semax peptide guide.
What Is Selank?
A peptide is a short chain of amino acids, the small building blocks of proteins. Selank has seven of them, in the order Thr-Lys-Pro-Arg-Pro-Gly-Pro, according to a 2018 review in Protein and Peptide Letters. The first four make up tuftsin, a natural immune peptide. The last three, Pro-Gly-Pro, are an added tail.
A 2008 paper in a Russian journal describes selank as a new peptide anxiolytic. An anxiolytic is a substance studied for easing anxiety. The same paper describes the compound as having completed the third phase of clinical testing. Phase 3 is the large final stage of testing before a medicine goes to regulators.
Here is where the evidence stands in the papers reviewed:
- What the studies show. There are real published human studies, and their results leaned in the same direction.
- What the studies are. The human studies are small, mostly from one country, and many include authors from the same Russian research groups that work on selank.
- What is still being studied. A 2021 review in the Journal of Clinical Pharmacology calls selank poorly studied and says compounds like it need proper study of misuse potential.
This guide sticks to published papers so that every number can be traced.
How Does Selank Work?
Nobody knows the full answer yet. The papers describe several ideas, and most of them come from lab work rather than from people.
- A GABA connection. GABA is the brain’s main calming signal. In a 2018 lab study, selank acted as a positive allosteric modulator of GABA binding, which means it nudged the way GABA attaches to brain cells, a bit like turning a dimmer switch. A 2016 study in Frontiers in Pharmacology found that selank changed the activity of 45 genes in the brain cortex of lab models within an hour. The authors suggested one possible cause is this GABA effect.
- A caution on that idea. A 2017 study in the same journal used nerve cells in a dish and found that selank alone did not change the GABA-related genes it tested. It did change how GABA and another compound acted when they were added together. So the GABA story is promising but not settled.
- The brain’s own painkiller chemicals. Enkephalins are natural chemicals that help the body handle stress and pain. In the 2008 Russian trial, a blood marker of enkephalin was lower in people with anxiety, and it rose during selank treatment, mostly in people with generalized anxiety disorder.
- An immune link. Because selank comes from an immune peptide, researchers also looked at immune messengers. A 2008 study found that selank changed the balance of two groups of immune signals in people treated for 14 days. In blood cells grown in a dish, it switched off activity of one immune messenger in people with depression but not in healthy controls.
- Brain connections. A 2020 study scanned the brains of 52 healthy people before and after a single dose of selank, Semax, or placebo. Both compounds changed how a fear-and-emotion center, the amygdala, connected with part of the temporal lobe. That study measured brain activity, not symptoms.
See also: Thymosin Alpha-1 and What Immune Research Examines
Reported Findings in Published Studies
These are the things the studies measured. They are research findings and not promises of any result.
- Anxiety scores. In the 2008 Russian trial, 62 people with generalized anxiety disorder or neurasthenia (a long-lasting tired and tense state) were split into two groups. Thirty got selank and 32 got medazepam, a standard anxiety medication. Doctors scored them on three rating scales, and the anxiety-easing effect of the two was similar.
- Less tiredness and more energy. The same paper reported that selank also had effects against weakness and tiredness and an energizing effect, which the paper did not report for medazepam.
- Fewer side effects from another medication. In a 2015 trial, 30 people took the sedative phenazepam alone and 40 took phenazepam plus selank. The combined group reached a better anxiety score sooner and had less trouble with attention, memory, sleepiness, and tiredness, both during treatment and after the sedative was stopped.
- Stress in lab models. In a 2017 study in lab models, a course of selank worsened anxiety measures less than a course of diazepam did, and under long-lasting stress the two together worked best.
- Mood in lab models. A 2008 study found that high repeated amounts counteracted depression-like behavior in one lab model.
All of these come with limits. The trials were small, the main papers are in Russian, and the rating scales are only one way to measure how a person feels.
See also: NAD+ Peptide Research and What It Shows About Longevity
What Is the Difference Between Selank and Semax?
Selank and Semax are often named together because they share the same three-amino-acid tail, Pro-Gly-Pro. They start from different places, though, and researchers study them for different things.
| Feature | Selank | Semax |
|---|---|---|
| What it is | A seven-amino-acid peptide | A seven-amino-acid peptide |
| What it is built from | Tuftsin, a natural immune peptide | A piece of ACTH, a stress-related hormone from the pituitary gland |
| Amino acid order | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Met-Glu-His-Phe-Pro-Gly-Pro |
| Main research focus | Anxiety, stress, and mental energy | Memory, learning, and brain protection after stroke |
| Brain growth factor (BDNF) | Not a main focus of the papers reviewed | Raised BDNF in a lab model and in people after stroke |
| Human studies reviewed | 62 people against medazepam, 70 people in an add-on trial, 52 healthy people in a brain scan study | 110 people after stroke, 187 people with poor brain blood flow, and the same 52-person scan study |
| Main limit | Small studies, mostly from one country | Small studies, mostly from one country |
BDNF is a protein that helps brain cells grow and connect. In a 2006 lab study, a single dose of Semax raised BDNF levels in a memory area of the brain by up to 1.4 times. In a 2018 study of 110 people after a stroke, those given Semax had higher BDNF in the blood and better recovery scores than those who were not given it.
Do Selank and Semax Help With Brain Fog and Anxiety in Research?
Brain fog is an everyday phrase for slow thinking, poor focus, and feeling mentally cloudy. It is not a medical measurement, and none of the papers reviewed measured it by name. What they did measure points to a few pieces of the picture.
Anxiety. This is where selank has the most human data. The anxiety scores in the 2008 and 2015 trials improved, as described above. Semax was not tested for anxiety in the papers reviewed.
Mental energy and attention. In the 2008 trial, selank was reported to ease tiredness and weakness. In the 2015 trial, adding selank to a sedative meant fewer problems with attention and memory than the sedative alone. Semax is the one linked with learning. A 2006 lab study reported more learned avoidance responses in a learning test along with the BDNF rise.
What the brain scans showed. In the 2020 study of 52 healthy people, both compounds changed the way the amygdala talked to the temporal lobe within 20 minutes of a single dose. The authors described general effects shared by the two and specific effects for each. A brain scan does not show that anyone felt calmer or sharper.
What is missing. There is no head-to-head trial of Selank against Semax. There is no trial that measured brain fog or focus in people with that complaint, and none that tested the two together for it. Any claim that they “clear brain fog” goes beyond what the papers show.
See also: What Is SS-31 Peptide and What Current Research Shows
Selank vs. Traditional Anxiety Medications
Traditional anxiety medications such as medazepam and phenazepam belong to a group called benzodiazepines. They boost GABA at a receptor on brain cells. A 2018 review of selank points out that these medicines come with known issues such as dependence and memory problems, which is why researchers look for gentler options.
| Comparison point | Selank research | Benzodiazepines such as medazepam |
|---|---|---|
| How it is thought to work | A nudge to the GABA system found in lab work, plus enkephalin and immune links | Direct boost of GABA at a brain cell receptor |
| Head-to-head human data | One 62-person Russian trial found a similar anxiety effect to medazepam | Used widely and studied for decades |
| Reported side effects | Added to phenazepam, it was linked with less sleepiness and fewer attention and memory problems | Sleepiness, memory problems, and dependence are well known |
| Quality of evidence | Small trials, mostly from one country, no independent copies found in the papers reviewed | Many large trials across many countries |
| Open questions | Misuse potential and long-term effects still need proper study | Known and managed in medical practice |
The comparison shows why selank draws interest and why more research is needed. A 2021 review says that compounds acting on GABA need proper study of misuse potential and withdrawal before public access. Nothing in the research suggests selank can stand in for any medication, and people who take medication for anxiety should speak with their prescriber.
Frequently Asked Questions
What is selank peptide?
Selank peptide is a seven-amino-acid chain built from tuftsin, a natural immune peptide, and studied mainly for anxiety and stress.
What does the research say about how well selank works?
Selank has published human studies, including a 62-person trial that found an anxiety effect similar to a standard medication, and a 2008 paper describes it as having finished phase 3 testing. The studies are small and mostly from one country, so the research is still early.
How does selank work?
The leading idea is a gentle effect on GABA, the brain’s calming signal, along with links to enkephalins and immune messengers. Lab results on the GABA idea are mixed, so the full picture is still open.
What is the difference between selank and Semax?
They share a Pro-Gly-Pro tail. Selank comes from an immune peptide and is studied for anxiety and stress. Semax comes from a piece of the stress hormone ACTH and is studied for memory, learning, and stroke recovery.
Does selank help with brain fog?
Brain fog was not measured in the papers reviewed. Selank was reported to ease tiredness and to cut attention and memory side effects of a sedative, but that is not the same thing.
Does selank help with sleep?
None of the papers reviewed measured sleep as an outcome. Calmer mood and better sleep are linked in daily life, but this research does not show a sleep effect.
Is selank safe?
Safety is not well established. The trials reported side effects of other medications going down when selank was added, but a 2021 review calls selank poorly studied and says compounds like it need proper study of misuse potential. Questions about regulatory status should go to qualified regulatory or legal advisers.
How is selank stored in the lab?
No tested shelf life for mixed selank appears in the papers reviewed. General laboratory habits for peptides are covered in the peptide reconstitution guide, and the supplier’s own paperwork is the best reference for any specific product.
Key Takeaways
- What it is. Selank is a seven-amino-acid peptide built from tuftsin, studied for anxiety, stress, and mental energy.
- Human evidence. One 62-person Russian trial found an anxiety effect similar to medazepam, and a 70-person trial found fewer side effects when selank was added to a sedative.
- Mechanism. Ideas include a gentle effect on GABA, enkephalins, and immune signals, mostly from lab work, and the GABA results are mixed.
- Selank vs. Semax. They share a Pro-Gly-Pro tail, but Selank is studied for anxiety and Semax for memory and stroke recovery.
- Evidence stage. The studies are small and mostly from one country, and a 2021 review calls selank poorly studied.
- Brain fog and sleep. Neither was measured by name, so claims about them go beyond the papers.
Research Use Disclaimer
This content is provided for Research Use Only (RUO). The compounds discussed are not drugs, dietary supplements, foods, or cosmetics, and are not intended for human or animal consumption, diagnostic use, or therapeutic use of any kind. They have not been evaluated by the FDA for safety or efficacy in humans. Any research use must be conducted by qualified professionals in a controlled laboratory environment, in accordance with all applicable institutional, local, and federal regulations.
Sources
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- Uchakina ON, Uchakin PN, Miasoedov NF, et al. Immunomodulatory effects of selank in patients with anxiety-asthenic disorders. Zh Nevrol Psikhiatr Im S S Korsakova. 2008.
- Medvedev VE, Tereshchenko ON, Kost NV, et al. Optimization of the treatment of anxiety disorders with selank. Zh Nevrol Psikhiatr Im S S Korsakova. 2015.
- Volkova A, Shadrina M, Kolomin T, et al. Selank administration affects the expression of some genes involved in GABAergic neurotransmission. Front Pharmacol. 2016.
- Filatova E, Kasian A, Kolomin T, et al. GABA, selank, and olanzapine affect the expression of genes involved in GABAergic neurotransmission in IMR-32 cells. Front Pharmacol. 2017.
- Kasian A, Kolomin T, Andreeva L, et al. Peptide selank enhances the effect of diazepam in reducing anxiety in unpredictable chronic mild stress conditions. Behav Neurol. 2017.
- Vyunova TV, Andreeva L, Shevchenko K, Myasoedov N. Peptide-based anxiolytics, the molecular aspects of heptapeptide selank biological activity. Protein Pept Lett. 2018.
- Sarkisova KIu, Kozlovskii II, Kozlovskaia MM. Effects of heptapeptide selank on genetically-based and situation-provoked symptoms of depression in behavior. Zh Vyssh Nerv Deiat Im I P Pavlova. 2008.
- Panikratova YR, Lebedeva IS, Sokolov OY, et al. Functional connectomic approach to studying selank and semax effects. Dokl Biol Sci. 2020.
- Doyno CR, White CM. Sedative-hypnotic agents that impact gamma-aminobutyric acid receptors, focus on flunitrazepam, gamma-hydroxybutyric acid, phenibut, and selank. J Clin Pharmacol. 2021.
- Dolotov OV, Karpenko EA, Inozemtseva LS, et al. Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the hippocampus. Brain Res. 2006.
- Gusev EI, Martynov MY, Kostenko EV, et al. The efficacy of semax in the treatment of patients at different stages of ischemic stroke. Zh Nevrol Psikhiatr Im S S Korsakova. 2018.
- Gusev EI, Skvortsova VI, Chukanova EI. Semax in prevention of disease progress and development of exacerbations in patients with cerebrovascular insufficiency. Zh Nevrol Psikhiatr Im S S Korsakova. 2005.
Explore the neuro and sleep research category for related research compounds. For related reading, see the Semax peptide guide, the DSIP research guide, and the peptide reconstitution guide.
