Selank

Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) engineered from the immune-active tetrapeptide tuftsin by adding a Pro-Gly-Pro tail to improve stability Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives+1. It was developed as an intranasal anxiolytic with additional nootropic and immunomodulatory effects, designed to reduce anxiety without the heavy sedation and muscle relaxation typical of benzodiazepines Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives+1.

Research has focused on generalized anxiety disorder, stress-related fatigue, and cognitive recovery after illness I.P. Ashmarin and Works on the Study of Neurotropic Activity of Regulatory Peptides+1. Originally created in Russia, Selank has been in medical use there since 2009 and was moved to over-the-counter status in 2017 due to favorable tolerability I.P. Ashmarin and Works on the Study of Neurotropic Activity of Regulatory Peptides. Outside Russia, it remains an unapproved research peptide, obtained through gray-market channels Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives.

Selank does not act like a classic benzodiazepine; instead, it shifts GABA receptor signaling in a positive allosteric manner, enhancing the calming effects of the brain's main inhibitory system without directly activating it Peptide-based Anxiolytics: The Molecular Aspects of Heptapeptide Selank Biological Activity+1. This is thought to produce anxiolysis while preserving alertness Combined Action of Benzodiazepine Tranquiizers and the Peptide Anxiolytic Selank on BALB/с Mice.

At the same time, Selank inhibits enkephalin-degrading enzymes, allowing natural pain-relieving and mood-modulating opioid peptides to remain active longer The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity+1. This may explain why research shows it can potentiate morphine analgesia and ease opioid withdrawal signs Selank, a Peptide Analog of Tuftsin, Attenuates Aversive Signs of Morphine Withdrawal in Rats+1.

Beyond these immediate effects, Selank influences longer-term brain adaptations: it increases brain-derived neurotrophic factor (BDNF) in the hippocampus, a protein critical for nerve health and stress resilience Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus in vivo+1. Functional brain scans in healthy humans have shown that intranasal Selank alters connectivity patterns in the amygdala and temporal cortex, confirming it reaches and modulates brain networks involved in emotion and cognition Functional Connectomic Approach to Studying Selank and Semax Effects.

Additional research points to Selank’s ability to regulate stress hormone levels, as seen in animal studies where it lowered elevated corticosterone during chronic stress, and to fine-tune immune signaling by changing cytokine gene expression Expression of inflammation-related genes in mouse spleen under tuftsin analog Selank+1. This combination of rapid neurotransmitter tuning and slower neurotrophic and immune adjustments accounts for the gradual, cumulative benefits often reported with regular use.

The research literature, while largely from Russian clinical groups, reports several consistent findings:

• Anxiolytic effect without sedation – In patients with generalized anxiety disorder, Selank provided comparable anxiety reduction to the benzodiazepine medazepam, but with anti-fatigue and mild psychostimulant effects rather than drowsiness [Optimization of the treatment of anxiety disorders with selank]+1. When added to phenazepam, it accelerated response and reduced side effects like sedation and cognitive dulling [Optimization of the treatment of anxiety disorders with selank].
• Anti-asthenic and cognitive support – Clinical studies in post-COVID patients found that a 30-day intranasal course improved asthenia, work capacity, anxiety, and depressive symptoms POST-COVID SYNDROME, POSSIBILITIES FOR THERAPY OF ASTHENIC DISORDERS WITH SELANK. Animal and human imaging work supports improvements in memory, stress-impaired cognition, and brain network connectivity Functional Connectomic Approach to Studying Selank and Semax Effects+1.
• Attentuation of opioid withdrawal – In animal models, a single 0.3 mg/kg dose reduced morphine withdrawal severity by nearly 40%, decreasing convulsions and improving physical signs Selank, a Peptide Analog of Tuftsin, Attenuates Aversive Signs of Morphine Withdrawal in Rats. Selank also enhanced morphine analgesia without causing pain relief on its own Selank effects on morphine-induced analgesia <i>in vivo</i> experiments.
• Stress adaptation and neuroendocrine regulation – In rats exposed to chronic restraint stress, Selank normalized anxiety- and depression-like behavior and lowered elevated corticosterone in a dose-dependent manner State of nervous system functions of Wistar rats when using peptide taftsin-PGP (selank) in restraint stress.
• Immune modulation – Selank and its metabolites alter the expression of chemokines, cytokines, and their receptors in the spleen, suggesting a systemic immunoregulatory role that may contribute to anti-inflammatory and antiviral effects observed preclinically Expression of inflammation-related genes in mouse spleen under tuftsin analog Selank+1.

Evidence for these effects is strongest for anxiety and asthenia in human studies (though limited in scale and geography) and well-supported for stress and immune modulation in animal models. The nootropic and opioid-related effects remain primarily preclinical.

Research protocols for Selank are predominantly intranasal, aligning with its design as a nose-to-brain delivery peptide Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives. Two key duration patterns emerge: a 14-day course for anxiety-spectrum disorders and a 30-day course for post-infectious asthenia [Optimization of the treatment of anxiety disorders with selank]+1. The total daily dose in these studies is typically 1.5 mg, divided into four administrations (2–3 drops each) [Optimization of the treatment of anxiety disorders with selank]+1.

Community protocols extend this framework: for acute stress, users often follow 250–500 mcg per dose, 2–3 times daily, for 10–14 days, while chronic cognitive fatigue or persistent anxiety may warrant a 2–4 week cycle. Off-cycles of equal length are common to preserve responsiveness [practitioner consensus].

Timing is flexible, but Selank’s non-sedating nature makes morning and early afternoon dosing ideal to avoid any residual activation that might disrupt sleep Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives. Some practitioners recommend taking a dose 15–30 minutes before anticipated stressors [practitioner consensus].

Selank is supplied as a lyophilized powder that requires mixing (reconstitution) with a diluent before use. For multi-dose vials, bacteriostatic water is recommended; for single-use or short-term use, sterile water is acceptable [practitioner consensus].

To reconstitute, slowly inject the diluent onto the inner wall of the vial, then swirl gently—never shake—to dissolve the powder. Avoid introducing air or contaminants by using sterile technique [practitioner consensus].

Storage: Lyophilized Selank should be kept at -20°C for long-term storage, or at 2–8°C for short-term storage before mixing. Once reconstituted, the solution must be refrigerated at 2–8°C. With bacteriostatic water, it is typically used within 30 days; with sterile water, best within 7–14 days. Freezing aliquots at -20°C can extend usability to about 2–3 months, but repeated freeze-thaw cycles should be avoided [practitioner consensus].

For intranasal use, transferring small aliquots into a sterile spray bottle every 1–2 weeks reduces contamination risk from repeated handling of the main vial [practitioner consensus].

The interactive calculator below can help determine specific volumes and concentrations based on your vial size and desired dose.

Interactions with other substances have been studied mostly in animals, but the pharmacological profile suggests several areas of caution:

• Benzodiazepines & other GABAergics – Selank can enhance the anxiolytic effect of diazepam and medazepam while reducing their sedative and muscle-relaxant side effects in mice Combined Action of Benzodiazepine Tranquiizers and the Peptide Anxiolytic Selank on BALB/с Mice+1. In human use, adding Selank to phenazepam reduced cognitive and sedative adverse events [Optimization of the treatment of anxiety disorders with selank]. However, combining Selank with alcohol, benzodiazepines, opioids, or other CNS depressants may increase the risk of severe respiratory depression, coma, and death Phenibut—an illegal food supplement with psychotropic effects and health risks.
• Opioids – Selank inhibited enkephalin-degrading enzymes and potentiated morphine analgesia in animals Selank effects on morphine-induced analgesia <i>in vivo</i> experiments+1. It also attenuated morphine withdrawal signs Selank, a Peptide Analog of Tuftsin, Attenuates Aversive Signs of Morphine Withdrawal in Rats. Caution is warranted when combined with prescription opioids or kratom; dose adjustments and monitoring for enhanced sedation or respiratory depression are advised [practitioner consensus].
• Anticoagulants – Selank demonstrated anticoagulant effects on thromboelastography Anticoagulant Effects of Arginine-Containing Peptides of the Glyproline Family (His-Phe-Arg-Trp-Pro-Gly-Pro and Thr-Lys-Pro-Arg-Pro-Gly-Pro) Revealed by Thromboelastography. Theoretical risk of increased bleeding when used with warfarin, heparin, antiplatelet drugs, or supplements that affect clotting (e.g., fish oil, ginkgo) Anticoagulant Effects of Arginine-Containing Peptides of the Glyproline Family (His-Phe-Arg-Trp-Pro-Gly-Pro and Thr-Lys-Pro-Arg-Pro-Gly-Pro) Revealed by Thromboelastography.
• Other nootropics – Selank is often combined with Semax for complementary anxiolytic and cognitive effects [community protocol]. However, stacking multiple nootropics may lead to overstimulation, insomnia, or irritability in some individuals.
• CNS stimulants – Selank’s mild psychostimulant and anti-fatigue properties may amplify the effects of stimulants like amphetamine or modafinil, potentially causing restlessness or sleep disruption Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives.

Selank is frequently included in research stacks for stress resilience, cognitive enhancement, and tissue recovery. Notable combinations include:

• Selank + Semax – A popular pairing where Selank provides anxiolysis and immune modulation, while Semax adds potent nootropic and neuroprotective effects via BDNF and neurotrophic pathways [community protocol]. Both are often administered intranasally.
• Selank + BPC-157 or TB-500 – Used when stress management and physical healing overlap. Selank addresses the psychological stress component, while the healing peptides support tissue repair [practitioner consensus].
• Selank + DSIP – DSIP (Delta sleep-inducing peptide) is used for sleep normalization; combining it with Selank may address daytime anxiety and nighttime sleep quality, but timing is important—Selank should be taken in the morning/afternoon, DSIP before bed [community protocol].
• Selank + Cerebrolysin – Some practitioners combine Selank with Cerebrolysin for intensive neurological support, as both influence neurotrophic factors and synaptic plasticity, though direct interaction data are lacking [practitioner consensus].

When stacking, introduce compounds one at a time and observe for overstimulation, headache, or sleep disturbances. Off-cycles are recommended to maintain sensitivity to the peptides [community protocol].

Selank is not FDA-approved nor approved by the European Medicines Agency. It is registered as a drug in Russia for mild anxiety disorders, where it has been available since 2009 and moved to over-the-counter status in 2017 I.P. Ashmarin and Works on the Study of Neurotropic Activity of Regulatory Peptides. In most Western countries, it is considered an unapproved neuroactive peptide and is sold only through gray-market channels, with products often labeled as 'research chemicals' Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives+1.

Its status in sports is clear: Selank is prohibited by the World Anti-Doping Agency (WADA). Reviews classify it under the 'brain doping' category, and it may fall under the open-ended prohibitions for unapproved substances or peptide hormones Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives+1. Athletes subject to testing should avoid it entirely.

Selank has a relatively benign side-effect profile in the limited clinical data available. The most commonly reported adverse effects are mild: transient nasal irritation (with intranasal use), dry mouth, and occasional daytime drowsiness Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives. Unlike benzodiazepines, it does not typically cause heavy sedation, muscle weakness, or cognitive dulling; in fact, it may reduce these effects when combined with such drugs [Optimization of the treatment of anxiety disorders with selank]+1.

However, the long-term safety picture is incomplete. Key concerns include:

• Anticoagulant activity – Selank has demonstrated blood-thinning effects in laboratory tests, so those with bleeding disorders or on anticoagulant therapy should exercise caution Anticoagulant Effects of Arginine-Containing Peptides of the Glyproline Family (His-Phe-Arg-Trp-Pro-Gly-Pro and Thr-Lys-Pro-Arg-Pro-Gly-Pro) Revealed by Thromboelastography.
• Immune modulation – It alters cytokine signaling and immune cell activity, which is theoretically beneficial but could exacerbate autoimmune conditions or alter infection responses Expression of inflammation-related genes in mouse spleen under tuftsin analog Selank+1.
• Opioid system effects – It potentiates morphine effects and reduces withdrawal, which may be risky in individuals with opioid use disorder Selank, a Peptide Analog of Tuftsin, Attenuates Aversive Signs of Morphine Withdrawal in Rats+1.
• Pregnancy and breastfeeding – No safety data exist; avoid use Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives.
• Lack of long-term data – No robust human studies beyond weeks to a few months are available, so extended continuous use is not supported Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives.

Monitoring should include baseline blood counts, coagulation profile if bleeding risk is present, and tracking of anxiety, mood, and sleep. Discontinue if significant agitation, bleeding, or immune flare-ups occur [practitioner consensus].