What is Selank?

What sources report

Structure and origin

Selank came out of the Institute of Molecular Genetics of the Russian Academy of Sciences, working with the V.V. Zakusov Research Institute of Pharmacology.² Its first four amino acids are tuftsin, the Thr-Lys-Pro-Arg fragment of the human immunoglobulin G heavy chain, and the added Pro-Gly-Pro tail makes the molecule more stable.² PubChem lists the formula C33H57N11O9 and a molar mass of 751.9 g/mol.²⁰ In rats, Selank (coded TP-7) showed stronger anti-anxiety and stimulant activity than tuftsin itself.²¹ A 2022 review counts it among 14 peptide drugs registered in Russia, classed there as an anxiolytic.²²

How it may work

Lab and animal work points to several possible mechanisms:

• Enkephalins: in human plasma tested in the lab, Selank slowed the enzymes that break down enkephalins, the body's own opioid peptides, with half-maximal inhibition near 15 micromolar.²³ The same paper found that enkephalins broke down faster in the blood of people with generalized anxiety.²³
• GABA: in binding tests on brain-cell membranes, Selank acted like a positive allosteric modulator of GABA receptors and blocked the modulating effect of diazepam and olanzapine.²⁴ In the rat brain cortex, 45 of 77 measurable nerve-signaling genes changed activity within 1 hour of a nasal dose of Selank or of GABA.²
• Serotonin and BDNF: in rats, a single injection raised serotonin turnover in the hypothalamus and brain stem for 30 minutes to 2 hours, and nasal Selank regulated BDNF, a nerve growth factor, in the hippocampus.¹²²⁵
• Immune signals: in the lab, Selank suppressed IL-6 gene expression in blood cells from people with depression but not in cells from healthy controls.²⁶
• Breakdown and delivery: blood enzymes cut Selank into fragments such as TKPRP, TKP, RP and GP.⁹ In rats, nasal dosing carried it into the brain better than injection into a vein or the abdomen, or delivery into the stomach.²⁷

The Russian label adds that nasal Selank reaches the blood within 30 seconds with 92.8% absolute bioavailability, and that blood levels fall over 5 to 5.5 minutes.⁷ It does not name the studies or species behind those figures.⁷

What human studies found

Five small human studies were found, all from Russia:

• 2008, anxiety: 62 adults with generalized anxiety disorder or neurasthenia took Selank (30) or the benzodiazepine medazepam (32).⁵ Anti-anxiety effects were similar, and Selank also had antiasthenic (anti-fatigue) and psychostimulant effects.⁵
• 2008, immune markers: in patients with generalized anxiety disorder or neurasthenia who took Selank for 14 days, blood tests showed shifts in the balance of Th1 and Th2 immune signals.²⁶
• 2014, anxiety: in 60 patients, Selank showed pronounced anti-anxiety and mild nootropic effects against phenazepam, and the effect lasted a week after the last dose.⁶
• 2015, add-on use: 70 patients took phenazepam alone (30) or with Selank (40).¹⁶ The combination responded earlier on the HDRS rating scale and caused fewer phenazepam side effects, such as memory problems, sedation and sexual problems.¹⁶
• 2020, healthy volunteers: 52 adults had brain scans before and 5 and 20 minutes after Selank, Semax or placebo, and Selank changed connectivity between the right amygdala and the right temporal cortex.¹⁸

The English abstracts of the patient studies do not describe randomization, blinding or doses.⁵⁶¹⁶ A ClinicalTrials.gov search in October 2026 found no Selank trial.²⁸ A 2021 US review called Selank a poorly studied Russian drug with GABA-related effects that is sold to US consumers as a dietary supplement, and a 2026 review grouped it with peptides whose online visibility may exceed the human evidence.¹³²⁹ Sources even disagree on whether clinical testing was completed. A 2020 Belgian medicines-lab paper said that, to its authors' knowledge, Selank had completed no clinical trials, while a 2008 Russian paper described it as having completed phase 3 testing.³⁰¹⁴

What animal studies found

• Anxiety: rats given daily injections for 4 weeks showed less anxiety-phobic behavior from day 2, with no change in body weight.¹⁷ Under unpredictable chronic mild stress, Selank combined with diazepam reduced anxiety most.³¹
• Withdrawal: in rats after long-term alcohol intake, one injection removed withdrawal anxiety without changing how much alcohol they drank.³² In morphine-dependent rats, one injection cut the withdrawal score by 39.6%, against 49.3% for diazepam.³³
• Memory: a single injection during training kept a learned food-reward task in memory more stably over 30 days, and a week of daily injections prevented memory and attention problems linked to long-term alcohol intake.¹²³⁴
• Mood: repeated high doses in WAG/Rij rats and single low doses in BALB/c mice had antidepressant-like effects.¹⁴
• Infection: added to cell cultures 24 hours before infection, Selank completely suppressed reproduction of influenza A virus, and in animals it switched on the interferon-alpha gene.¹⁵
• Monkeys: nasal Selank produced lasting reductions in fear and aggression in monkeys with experimentally induced neurosis.³⁵

For laboratory work, buy Selank as a freeze-dried research vial. Related research is mapped in Peptides and focus and memory and Peptides and sleep. See also What is DSIP?.

Side effects

Data on side effects are sparse.³¹⁶ The Russian label for the nasal drops lists allergic reactions, including delayed ones, and an unpleasant taste when drops run into the throat, without saying how often either occurs.³⁷ The drops contain methylparaben at 1 mg per mL, a preservative the label says can cause allergic reactions.³ The trial abstracts discuss tolerability only in general terms and give no side-effect rates for Selank.⁶¹⁶

The label lists hypersensitivity, pregnancy, breastfeeding and age under 18 as contraindications, noting that no clinical studies were done in children or in pregnancy.³ It also states that Selank causes no dependence or habituation, does not affect driving, has no registered overdose cases and showed no interactions with haloperidol, pentobarbital, hexobarbital, analeptics or alcohol. These are manufacturer statements for the nasal product.³ FDA warns that compounded selank acetate may trigger immune reactions and says it lacks important safety information for people.⁸ Health Canada adds that unauthorized injectable drugs may cause infection and allergic reactions, and may contain ingredients or contaminants not on the label.³⁶

Dosage information

No human dose of Selank is established: there is no FDA-approved dose, and no approved or published human dose for injection was found.⁴³ The only regulator-approved Selank product found is Russia's 0.15% nasal solution, which holds 1.5 mg of selank diacetate per mL; its directions belong to that product alone and are not a dose for any other form.³⁷ The English abstracts of the 2008, 2014 and 2015 patient trials do not state the dose or route used.⁵⁶¹⁶ Rat studies most often used 0.3 mg/kg (300 micrograms/kg) by injection into the abdomen, once or daily for up to 4 weeks.¹⁷³²³³ In depression models, mice received single injections of 100 or 300 micrograms/kg and rats received repeated injections of 1,000 to 2,000 micrograms/kg.¹⁴ These are animal doses, not doses for people.

Reconstitution and storage

Russia's medicine needs no mixing: it is a ready-made solution of selank diacetate in purified water with methylparaben added.⁷³ Its label says to keep bottles at 2 to 8 °C away from light without freezing, to use an opened bottle within 15 days at up to 25 °C, and gives a 2-year shelf life.³⁷ No label or study found gives reconstitution steps for Selank powder vials.³⁷

For freeze-dried peptides in general, GenScript advises storage at -20 °C away from bright light, and Selank's lysine and arginine are among the amino acids it flags for pulling moisture from the air.³⁷¹ Bachem's general advice is not to hold peptides in solution at all, and to freeze single-use portions when there is no alternative.³⁸ The lab steps are in How to reconstitute a peptide vial, and storage basics are in How to store peptides.

Regulatory status

United States: Selank is not FDA-approved.⁴ In a 1 April 2020 warning letter, FDA told a Kentucky compounding pharmacy that drugs it made from Selank, Semax, BPC 157 and other substances did not qualify for the compounding exemptions. The substances had no USP or NF monograph, were not part of an approved drug and were not on the 503A bulks list.³⁹ A 2021 warning letter noted that Selank had not been nominated for that list.⁴⁰ FDA's page on substances that may present significant safety risks now shows Selank acetate (TP-7) among category 2 nominations later withdrawn by their nominators.⁸ Selank was not among the seven peptides FDA's Pharmacy Compounding Advisory Committee discussed on 23 and 24 July 2026.⁴¹

Russia: Selank 0.15% nasal drops hold registration LP-No(010951)-(RG-RU), dated 15 July 2025 and listed as valid indefinitely, under ATC code N05BX (other anxiolytics).⁷ They are sold without a prescription for adults with anxiety states and for preventing and treating stress disorders.³

Canada and Europe: Health Canada's 1 August 2025 advisory on peptides seized from and sold by Canada Peptide named Selank, and stated that injectable peptides are regulated as prescription drugs in Canada.³⁶ A Belgian medicines lab found Selank in preparations seized in 2017 and 2018 and reported that such peptides were sold freely online as injection powder or in nasal sprays.³⁰

Sport: Selank is not named on WADA's 2026 Prohibited List.¹⁰ Class S0 bans substances with no current government approval for human therapeutic use, and Selank holds a Russian registration.¹⁰³ Reviews disagree: a 2025 review listed its status as unclear, while a 2026 review stated that WADA prohibits it.¹¹⁴