Selank (anxiolytic use)

Selank is tuftsin, an immunoactive IgG-derived tetrapeptide, with a Pro-Gly-Pro tail bolted on to slow enzymatic breakdown. Its anxiolytic effect is attributed mainly to inhibition of enkephalin-degrading enzymes, which raises endogenous enkephalin tone, and to changes in expression of GABA-A receptor subunits in the hippocampus and amygdala rather than direct receptor agonism. That indirect mechanism is the best explanation for the clinical picture — anxiolysis without sedation, without motor impairment and without a withdrawal syndrome. Additional reported effects on BDNF expression, serotonin turnover and interleukin-6 are consistent but less firmly pinned down. Sleep improvement is generally secondary: lowering pre-sleep anxious arousal, not producing sleep pressure.

Targets: Enkephalin-degrading enzymes, GABA-A receptor subunit expression, Serotonergic and monoamine turnover, BDNF expression, Interleukin-6 and immune signalling

• · The registered Russian product is a 0.15% solution delivering roughly 75 mcg per drop, given as 2 to 3 drops per nostril three times daily. This is substantially higher than most Western community dosing.
• · Most people run well below the Russian clinical dose and still report an effect. Start at 250 mcg and see whether you need more before scaling toward the clinical range.
• · Less common and outside the registered route. Because injection bypasses nasal losses entirely, use noticeably less than the intranasal number.

Work out your exact syringe units →

• commonNasal irritation, burning or a running nose— The dominant complaint with the intranasal route.
• commonDysgeusia - a metallic or bitter taste as the spray drains— Harmless and unavoidable with nasal peptides.
• uncommonMild fatigue or flatness— Some people describe emotional blunting rather than calm, particularly at higher doses.
• uncommonHeadache— Usually early in a course.
• rareParadoxical irritability— Reported by a minority; typically resolves on stopping.

• Pregnancy and breastfeeding - no safety data.
• Do not treat it as a replacement for prescribed treatment of a diagnosed anxiety disorder without a plan; the Russian trials compared it to benzodiazepines in supervised settings.
• Active nasal infection or damaged nasal mucosa - use a different route until it heals.

• synergydsip — A sensible pairing when insomnia is driven by racing thoughts rather than by circadian misalignment.
• synergysemax — The classic Russian nasal stack — Semax for drive and focus in the morning, Selank for anxiety control.
• synergyepitalon-circadian — Non-overlapping mechanisms: one addresses arousal, the other addresses rhythm.
• cautionorexin-a-wake — Orexin signalling is strongly implicated in panic and anxiety; pushing it up while trying to bring anxiety down works against itself.

• · Use a simple repeated anxiety scale such as GAD-7 at baseline, day 7 and day 14 - the effect is gradual enough that memory alone will mislead you.
• · Track sleep onset latency if sleep is the target, since that is where an anxiolytic effect shows up first.
• · No bloodwork is established or required.

Registered as a prescription medicine in Russia. Not approved in the US, UK or EU, where it is sold as a research chemical.

• Zozulya et al. 2008, Selank versus medazepam in generalised anxiety disorder (trial)
• Medvedev et al., Selank in anxiety disorders with asthenic features (trial)
• Kolomin et al., transcriptomic effects of Selank in rat brain (preclinical)
• Semenova & Kozlovskaya, tuftsin analogue Selank pharmacology review (review)

Selank is a rare case where the mechanism actually explains the clinical picture, which is why it is worth going into properly. The opioid arm is the best-supported piece. Kost, Sokolov, Zozulia and colleagues showed in 2001 that Selank inhibits enkephalin-degrading enzymes in human serum, and Zolotarev's group followed with tritium-labelled Leu-enkephalin work in 2004 confirming the inhibition directly. This is not receptor agonism. Selank does not bind opioid receptors; it slows the breakdown of your own enkephalins, which raises endogenous enkephalin tone. Zozulia's 2008 clinical trial measured serum enkephalin in patients and found it was low in proportion to symptom severity and rose after Selank treatment, with the rise correlating with improvement in generalised anxiety disorder patients. That is an unusually clean translational chain: enzyme inhibition in vitro, enkephalin rise in patients, correlation with response. Kozlovskii's 2012 work found the anxiolytic effect had an opioid-dependent component, and Meshavkin's 2006 study found a naloxone-blockable effect on dopaminergic behaviour, both consistent with the same story. The GABA arm is different and more recent. Volkova, Shadrina, Kolomin and colleagues published in Frontiers in Pharmacology in 2016 showing that Selank at 300 mcg/kg changed expression of 45 of 84 neurotransmission-related genes in rat frontal cortex at one hour, with 22 still altered at three hours, and that the pattern correlated positively with the changes produced by GABA itself. Their conclusion was allosteric modulation of the GABAergic system. Note carefully what this is and is not: it is a change in transcription of genes encoding GABA-A subunits and related machinery, not direct receptor binding. Selank is not a benzodiazepine site ligand. That distinction is the entire explanation for the clinical profile - a compound that shifts the expression of the GABA system over hours to days does not produce the acute sedation, motor impairment, amnesia or withdrawal syndrome that a compound occupying the benzodiazepine site does. Which also explains the two-phase time course everyone reports. Something happens in the first 15 to 45 minutes after a nasal dose, which is too fast for transcription and is probably the enkephalin effect. And something else consolidates over 10 to 14 days, which is the timescale the Russian trials used and the timescale on which expression changes would compound. Dosing Selank once and concluding it does not work is a category error. The immune arm is real but usually overstated in marketing. Uchakina, Uchakin, Miasoedov and colleagues reported in 2008 that Selank at 10 nanomolar completely suppressed IL-6 gene expression in peripheral blood cells from depressed patients but not from healthy controls, and shifted Th1/Th2 cytokine balance over 14 days in patients with generalised anxiety and neurasthenia. Interesting, plausibly relevant to the fatigue and asthenia component, and not a reason to take it for immune function. Sleep, finally, is downstream. Selank is not a hypnotic and produces no sleep pressure. It improves sleep in people whose sleep is wrecked by pre-sleep anxious arousal, by removing the arousal. If your problem is that you fall asleep fine and wake at 4am, this is the wrong compound.

The dominant failure is dosing once, feeling a mild calm for two hours, and concluding it is a weak compound. The Russian trials dosed for 14 days and the enkephalin and gene expression changes both need that time. Selank taken as an as-needed pill for a stressful afternoon is being used as something it is not. It works as one, but you are getting maybe a quarter of what it does. The second is the dose gap. Most Western users run 250 to 750 mcg a day. The registered Russian product delivers roughly 900 to 2700 mcg a day. That is a three to seven-fold gap between what people take and what was actually trialled, and it means a lot of people who say Selank did not work for them never reached a studied dose. If a two-week block at 500 mcg does nothing, the answer is to go up, not to give up. The third is nasal irritation, and it is mostly self-inflicted. Overconcentrated solution, too much volume per spray, the same nostril every time, and a bottle left at room temperature on a desk for six weeks. A 10 mg vial in 2 mL gives 5 mg/mL, so a 100 microlitre actuation is 500 mcg - convenient arithmetic, but verify it against your specific pump because they vary. Alternate nostrils. Keep the bottle in the fridge and treat any bottle kept at room temperature as a two-week item. The fourth is emotional blunting rather than calm. A minority describe flatness, mild fatigue or indifference instead of anxiolysis, and it is more common at the higher end. This is a signal to reduce, not to persist. The fifth, and the one that matters most: using Selank to avoid treating a diagnosed anxiety disorder. The trials that make this compound interesting compared it to benzodiazepines in supervised clinical settings with proper scales and follow-up. Running it alone off a research-chemical vial for severe GAD, panic disorder or PTSD is using the evidence to justify something the evidence does not cover. It also has no evidence in acute panic, where it is unlikely to help at all. The small one: paradoxical irritability. Rare, resolves on stopping, no known predictor.

1. 250 mcgDays 1 to 7 — One 250 to 300 mcg intranasal dose, split between nostrils, taken at the time of day your anxiety is worst - or 1 to 2 hours before bed if sleep is the target. Do not judge it on day one. The acute calming is real but modest; the effect you are actually waiting for takes a week.
2. 500 mcgDays 8 to 14 — If a full week at 250 mcg has not moved your baseline, go to 500 mcg daily - either as one dose or split morning and evening. Splitting is closer to how the Russian protocol works.
3. 900 mcgDays 15 to 21 — Approaching the bottom of the registered Russian clinical range, typically split into two or three doses across the day. Most Western users never need to get here.
4. 1.8 mgIf escalating to the full clinical range — The registered Russian product is a 0.15% nasal solution at roughly 75 mcg per drop, given as 2 to 3 drops per nostril three times daily, which lands between about 900 and 2700 mcg a day. This step is the middle of that. It is where the trial data actually sits, and it is three to seven times what most people use.
5. 2.7 mgCeiling — The top of the registered clinical dose. There is no reason to go above this and no data above it. If 2700 mcg daily for two weeks does nothing, stop.

• Enkephalin-degrading enzymes in human serum — Inhibition demonstrated in human serum; no Ki reported that I could resolve

  The best-evidenced Selank target. Inhibiting enkephalin breakdown raises endogenous enkephalin tone. Demonstrated in vitro (Kost et al. 2001, Zolotarev et al. 2004) and confirmed as a rise in serum enkephalin in treated patients that correlated with clinical response (Zozulia et al. 2008).

• GABA-A receptor system (expression-level, not direct binding) — Not a binding interaction - no benzodiazepine-site or GABA-site affinity has been demonstrated

  Selank alters expression of genes encoding GABAergic neurotransmission machinery in rat frontal cortex within one to three hours, in a pattern correlating with GABA's own effect (Volkova et al., Front Pharmacol 2016). The authors describe this as allosteric modulation of the GABAergic system. This is the mechanism behind anxiolysis without sedation.

• Opioid receptor systems (indirect) — No direct binding demonstrated

  The anxiolytic effect has a naloxone-sensitive component (Kozlovskii et al. 2012), and Selank's effect on apomorphine-induced dopaminergic behaviour is naloxone-blockable (Meshavkin et al. 2006). Consistent with an indirect opioid action via raised enkephalin, not with direct receptor agonism.

• IL-6 gene expression in peripheral blood mononuclear cells — Effective at 10 nanomolar in vitro

  Suppressed IL-6 gene expression in cells from depressed patients but not healthy controls, and shifted Th1/Th2 balance over 14 days of clinical dosing (Uchakina et al. 2008). A state-dependent immunomodulatory effect rather than a general immune stimulant.

• BDNF expression and monoamine turnover — Not characterised

  Reported in rodent work from the originating group. Plausible and consistent with the antiasthenic and mild psychostimulant profile described in the clinical trials, but the least firmly established of the mechanisms listed here.

• Zozulia, Neznamov, Siuniakov et al. - efficacy and possible mechanisms of action of the peptide anxiolytic selank in generalised anxiety disorder and neurasthenia (Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova 2008) Randomised active-comparator clinical trial (not phase-labelled in the Western sense) · n=62 · 2 weeks · 2008

  Anxiolytic efficacy of Selank (n=30) versus the benzodiazepine medazepam (n=32) in generalised anxiety disorder and neurasthenia, with serum enkephalin as a mechanistic secondary. Both drugs produced comparable anxiolysis; Selank additionally produced antiasthenic and mild psychostimulant effects that medazepam did not. Enkephalin levels were depressed in proportion to symptom severity at baseline and rose after Selank, with the rise correlating with improvement in the GAD group.

• Uchakina, Uchakin, Miasoedov et al. - immunomodulatory effects of selank in patients with anxiety-asthenic disorders (Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova 2008) Clinical observation with in vitro component, not phase-labelled · 2 weeks · 2008

  Cytokine response to Selank in patients with generalised anxiety disorder and neurasthenia over 14 days. Selank at 10 nanomolar completely suppressed IL-6 gene expression in peripheral blood cells of depressed patients but not healthy controls, and altered Th1/Th2 balance clinically.

• Medvedev, Tereshchenko, Kost et al. - optimisation of the treatment of anxiety disorders with selank (Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova 2015) Comparative clinical trial, not phase-labelled · n=70 · 2015

  Phenazepam monotherapy (n=30) versus phenazepam plus Selank (n=40) in anxiety-spectrum disorders. The combination reached a therapeutic effect on HDRS faster and substantially reduced benzodiazepine side effects - attention and memory impairment, asthenia, sedation, excessive sleep, sexual dysfunction, emotional indifference and orthostatism. Assessed with HDRS, CGI, Spielberger, UKU, Stroop, verbal fluency and SF-36.

15 to 45 minutes after the first nasal dose: a noticeable reduction in anxious arousal. Described consistently as the edge coming off rather than sedation - no drowsiness, no motor slowing, no cognitive fog. Some people feel nothing at all on day one at 250 mcg. 2 to 4 hours: the acute effect fades. This is why the Russian protocol splits the daily dose across two or three administrations rather than giving it all at once. Days 3 to 7: the first sign of a shifted baseline - fewer anxious episodes rather than shorter ones. This is where the gene expression story would start to show up if it is real. Days 10 to 14: the point at which the clinical trials measured their primary endpoints, and the point at which you should judge whether it works. GAD-7 at day 14 against your baseline is the honest test. If sleep is the target, sleep onset latency is the first thing to move. Days 14 to 21: the antiasthenic and mild psychostimulant effects Zozulia described - improvement in fatigue and drive as distinct from anxiety - tend to be reported later than the anxiolysis. Stopping: no withdrawal syndrome, no rebound anxiety and no dependence has been described across the Russian clinical experience, which is the headline advantage over benzodiazepines. The effect fades over days rather than reversing abruptly. Repeat courses: the protocol is a defined 14 to 21 day course followed by a break. Occasional as-needed use between courses is reasonable given the safety profile, but open-ended continuous daily dosing is not how the compound was studied and nobody has looked at what a year of it does.

Selank stacks well because it does not sedate, does not compete for the benzodiazepine site and has no dependence liability. That is a rare combination. With Semax: the classic Russian nasal pair, and both are registered medicines there. Semax in the morning for drive and focus, Selank in the afternoon or evening for anxiety control. They come from the same institute, share the enkephalinase-inhibition mechanism (Kost's 2001 paper covers both), and are routinely prescribed together. If you run both, keep at least a few hours between doses and do not put them in the same bottle - you will lose all ability to titrate either. With DSIP: the best pairing on this site for anxiety-driven insomnia specifically. Selank 250 to 500 mcg intranasally 1 to 2 hours before bed takes down the pre-sleep arousal; DSIP 100 to 200 mcg subcutaneously 30 to 60 minutes before lights out handles the sleep itself. Different mechanisms, no additive sedation, no morning hangover from either at these doses. With a benzodiazepine: the Medvedev 2015 study is directly about this and the result was favourable - faster response on HDRS and markedly fewer benzodiazepine side effects when Selank was added to phenazepam. If you are on a prescribed benzodiazepine, this is the single stack with actual supporting human data. It is also the one where you should be talking to whoever prescribes it, because the sensible use of that finding is dose reduction, not addition. With an SSRI or SNRI: no interaction data at all. Mechanistically there is no obvious conflict - Selank is not a serotonergic drug in any direct sense - but the reported effects on monoamine turnover mean this is genuinely uncharacterised territory. If you are on a serotonergic antidepressant, the honest position is that nobody knows. With Epitalon: non-overlapping. One addresses arousal, the other addresses rhythm. Fine to run together and easy to attribute effects because the timescales differ. Against orexin-A: this is the one to avoid. Orexin signalling is directly implicated in panic circuitry and raises anxious arousal; Selank exists to lower it. Running both is paying twice to end up where you started. A note on nasal real estate: if you are running Semax and Selank both intranasally, you are putting a lot of volume through a limited mucosa. Alternate nostrils, keep total volume per actuation to about 100 microlitres, and give the mucosa a break if it starts to feel raw. Nasal irritation is the most common complaint with this compound and it is largely a volume and frequency problem.

Against a benzodiazepine: this is the comparison the compound was built for, and it held up in the one head-to-head that exists. Selank produced comparable anxiolysis to medazepam over 14 days in 62 patients, with no sedation, no motor impairment, no amnestic effect, no dependence and no withdrawal, plus antiasthenic and mild psychostimulant effects the benzodiazepine did not have. The caveats are large - one small trial, Russian, from the institute that developed it, never independently replicated in the West. But it is a real randomised active-comparator trial and it puts Selank in a different evidential category from most of this site's catalogue. Against an SSRI: not comparable and not competing. SSRIs have hundreds of trials, take four to six weeks, and treat disorders. Selank has a handful of trials, takes two weeks, and was studied in generalised anxiety and neurasthenia. If you have diagnosed GAD, the SSRI is the higher-expected-value treatment and Selank is the thing you might add to it - with the caveat that nobody has studied that combination. Against Semax: same institute, same enkephalinase mechanism, opposite ends of the arousal axis. Semax is for drive, focus and cognitive fatigue. Selank is for anxiety. They are complements, not alternatives. Against L-theanine, ashwagandha or magnesium: all cheaper, all oral, all with weaker but non-zero evidence. If you have not tried 200 mg L-theanine or a proper KSM-66 ashwagandha trial, do that before buying a nasal peptide, purely on cost. Against DSIP for sleep: entirely different problems. DSIP is for sleep itself. Selank is for the anxiety that is preventing sleep. Diagnose which one you have before choosing. Within this site's catalogue: Selank sits at the top of the evidence hierarchy in the sleep and mood class alongside Epitalon, and above it on trial quality. It is a registered prescription medicine in a country with a real regulator, with a randomised active-comparator trial and a mechanistic chain that runs from in vitro enzyme inhibition to a measured biomarker change in patients. That is genuinely more than almost anything else here has. It is still small, monocentric, and unreplicated outside Russia, and that limitation should not be waved away.

$30–$110/month. A 10 mg vial covers roughly 13 to 40 days at typical community doses of 250 to 750 mcg daily, and a good deal less if you run the full Russian clinical range of 900 to 2700 mcg daily. Russian pharmacy nasal drops, where obtainable, are often cheaper per milligram than research-chemical vials. Indicative retail observations, not sourced or surveyed pricing.

• ?No human pharmacokinetic study of intranasal Selank exists. The tmax of roughly 0.5 hours in this record is inferred from reported onset of effect, not from a measured plasma concentration curve.
• ?Intranasal bioavailability has never been quantified. The route comparison that supports nasal delivery (Ashmarin 2008) was done in rats with tritium-labelled peptide and reports relative CNS penetration, not a percentage.
• ?The subcutaneous dose range of 100 to 300 mcg is a community convention with no published basis. It rests on the reasonable assumption that injection avoids nasal losses, but the size of that adjustment is guesswork.
• ?Nearly all clinical evidence comes from the Institute of Molecular Genetics and associated Moscow centres - the group that developed the compound. There is no independent Western replication of any clinical finding.
• ?The Zozulia, Uchakina and Medvedev trials are published in Russian. Titles, authors, journals, sample sizes and abstract-level results were verified through PubMed in this session; the full texts were not read, so effect sizes, blinding details, randomisation methods and dropout rates are not characterised here.
• ?Duration of the Medvedev 2015 add-on study was not stated in the abstract.
• ?No Ki or IC50 for Selank against any specific enkephalin-degrading enzyme could be resolved.
• ?The GABAergic mechanism is an expression-level finding in rat frontal cortex at a single dose (300 mcg/kg). Whether it occurs at human doses, in human brain, or on the timescale of clinical response is unknown.
• ?How much of Selank's activity is attributable to the Pro-Gly-Pro tail rather than the parent peptide has not been resolved, and Pro-Gly-Pro has independent pharmacology.
• ?There is no interaction data with SSRIs, SNRIs, or any serotonergic drug, despite reported effects on monoamine turnover.
• ?No long-term safety data beyond the 14 to 21 day course length exists. Nobody has published on a year of continuous use.
• ?There is no evidence in acute panic, PTSD or social anxiety disorder specifically - the trials were in generalised anxiety disorder and neurasthenia.
• ?The 751.9 Da molecular weight was confirmed by calculation from the TKPRPGP sequence rather than from a cited analytical measurement.
• ?Cost figures are indicative retail observations, not sourced or surveyed data.

• Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia Zozulia AA, Neznamov GG, Siuniakov TS, Kost NV, Gabaeva MV, Sokolov OYu, et al., Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 2008 · PMID 18454096

  108(4):38-48. The head-to-head against medazepam in 62 patients. This is the single most important human study on Selank and the reason it is a registered medicine in Russia rather than another forum peptide.

• Semax and selank inhibit the enkephalin-degrading enzymes from human serum Kost NV, Sokolov OYu, Gabaeva MV, Grivennikov IA, Andreeva LA, Miasoedov NF, Zozulia AA, Bioorganicheskaya Khimiya (Russian Journal of Bioorganic Chemistry), 2001 · PMID 11443939

  27(3):180-3. The primary mechanistic paper for the enkephalinase inhibition arm, done in human serum rather than rodent tissue.

• Leu-enkephalin homogeneously labeled with tritium in studying the Selank inhibiting effect on enkephalin-degrading enzymes Zolotarev YuA, Sokolov OYu, Kost NV, Vaskovsky BV, Miasoedov NF, Zozulia AA, Bioorganicheskaya Khimiya, 2004 · PMID 15344652

  30(3):234-40. Direct radiolabelled confirmation of the enkephalinase inhibition.

• Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission Volkova A, Shadrina M, Kolomin T, Andreeva L, Limborska S, Myasoedov N, Slominsky P, Frontiers in Pharmacology, 2016 · PMID 26924987

  7:31. Open access, in English, and the clearest statement of the GABAergic expression mechanism. 45 of 84 neurotransmission genes altered at one hour in rat frontal cortex, correlating with GABA's own signature.

• Immunomodulatory effects of selank in patients with anxiety-asthenic disorders Uchakina ON, Uchakin PN, Miasoedov NF, Andreeva LA, Shcherbenko VE, Mezentseva MV, Gabaeva MV, Sokolov OYu, Zozulia AA, Ershov FI, Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 2008 · PMID 18577961

  108(5):71-5. The IL-6 and Th1/Th2 findings, and the source of the state-dependent immune claim.

• Optimization of the treatment of anxiety disorders with selank Medvedev VE, Tereshchenko ON, Kost NV, Ter-Israelyan AY, Gushanskaya EV, Chobanu IK, Sokolov OYu, Myasoedov NF, Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 2015 · PMID 26356395

  115(6):33-40. The add-on study. Practically the most useful trial in the set, because it addresses the real-world question of whether Selank lets you use less benzodiazepine.

• The role of the opioid system in the peculiarities of the anti-anxiety effect of the peptide anxiolytic selank Kozlovskii II, Andreeva LA, Kozlovskaya MM, Nadorova AV, Kolik LG, Eksperimentalnaya i Klinicheskaya Farmakologiya, 2012 · PMID 22550852

  75(2):10-3. Establishes the opioid-dependent component of the anxiolytic effect.

• Naloxone-blocked depriming effect of anxiolytic selank on apomorphine-induced behavioral manifestations of hyperfunction of the dopamine system Meshavkin VK, Kost NV, Sokolov OYu, Zolotarev YuA, Myasoedov NF, Zozulya AA, Bulletin of Experimental Biology and Medicine, 2006 · PMID 17415472

  142(5):598-600. Further evidence that Selank's effects run through the endogenous opioid system rather than around it.

• A comparative analysis of the distribution of glyprolines administered by various routes Ashmarin IP, Baglikova KE, Edeeva SE, Zolotarev YuA, Andreeva LA, Kost NV, Zozulia AA, Samonina GE, Miasoedov NF, et al., Bioorganicheskaya Khimiya, 2008 · PMID 18695718

  34(4):464-70. The route comparison. Tritium-labelled Selank and Pro-Gly-Pro given intraperitoneally, intranasally, intragastrically and intravenously in rats - intranasal gave the best CNS penetration, which is the closest thing to a pharmacokinetic justification for the nasal route that exists.

• Evenly tritium-labeled peptides and their in vivo and in vitro biodegradation Zolotarev YuA, Dadayan AK, Dolotov OV, et al., Bioorganicheskaya Khimiya, 2006 · PMID 16637290

  32(2):183-91. Degradation kinetics for this family of peptides, and the basis for saying the Pro-Gly-Pro tail slows but does not prevent breakdown.