Selank: what the studies show, status and safety

Summary

Selank is a laboratory-made chain of seven amino acids. Its front half copies tuftsin, a small immune peptide the body cuts out of an antibody; the back half was added to stop enzymes destroying it. Russia has licensed it as nasal drops since 2009, and sells it there without a prescription. Nowhere else is it approved. Five human studies exist, covering roughly 250 people, none of them registered and none of them blinded. In April 2026 the US Food and Drug Administration recorded that it lacks important information about the safety of Selank in people.

Key findings at a glance

• Approved in one country, and sold there over the counter. The Russian register carries nasal drops under number ЛСР-003338/09 from the end of April 2009, marked for supply without a prescription ^[1], ^[2].
• Zero registered clinical trials. Five different searches of ClinicalTrials.gov on 6 September 2026 returned no genuine Selank study. The apparent hits are text coincidences ^[3].
• Five human studies, roughly 250 people. Three clinical comparisons enrolled 62, 60 and 70 patients, a brain-scan study 52 healthy volunteers, and one open study gave no participant count at all ^[4], ^[5], ^[6], ^[7], ^[8].
• No dummy treatment in any clinical study. All three comparisons ran against Russian sedatives, with no blinding described and no entry in any register ^[4], ^[5], ^[6].
• Two side effects on the label, both without a frequency. For a medicine on sale since 2009, that is a sign of missing data rather than of safety ^[1].
• The FDA has an open safety note on it. Selank acetate sits on the agency's list of bulk substances that may present significant safety risks, in the table of substances whose nomination was withdrawn. The entry warns of possible immune reactions and says the agency lacks important safety information about the substance in people ^[9].
• Its position in sport is unresolved. Selank is not named on the 2026 prohibited list, and the catch-all clause for unapproved substances may not fit, because a national health authority has approved it ^[10].

What it is

Selank is a synthetic heptapeptide, meaning a short chain of seven amino acid building blocks. The first four of them are tuftsin, a natural peptide that the body releases from the heavy chain of immunoglobulin G, one of the antibodies. Tuftsin on its own is destroyed by tissue enzymes within moments ^[11].

The remaining three links, proline, glycine and proline, are not part of tuftsin at all. They were attached deliberately. Chains ending in proline are awkward for many peptide-splitting enzymes to grip, so the tail buys the molecule time. Selank is tuftsin plus a shelf life ^[11], ^[12].

The work was done in Moscow, at the Institute of Molecular Genetics of the Russian Academy of Sciences together with the Zakusov Institute of Pharmacology. The same names recur on the papers from 1995 to the present day. The finished medicine is made and marketed by Peptogen, a Moscow company that is also the licence holder ^[1], ^[2], ^[12].

Quick facts

How it works

Nobody has shown how Selank works in a person. Every idea below comes from test tubes, membrane preparations, brain slices or animals, and almost all of it from the groups that created the molecule.

• Slowing the breakdown of the body's own opioids. In human serum Selank held back the enzymes that destroy enkephalins, with half of the activity blocked at 20 micromoles per litre, and at 15 micromoles per litre in plasma. That is stronger than the reference blockers bacitracin and puromycin ^[15], ^[16].
• Nudging the calming signal. In a binding study on brain cell membranes, Selank behaved as a positive allosteric modulator at the GABA receptor. In plain terms it does not occupy the site itself; it may make the brain's main calming transmitter work better. It also blocked the same effect from diazepam and olanzapine ^[17].
• Shifting gene activity. An hour after a dose, 45 of 84 genes involved in nerve signalling had changed their activity in the rat frontal cortex, and 22 were still changed at three hours. The pattern resembled that of GABA itself ^[18].
• Raising inhibitory traffic in the hippocampus. In rat brain slices Selank increased the size and rate of the inhibitory currents that quieten pyramidal cells. Between 1 and 8 micromoles per litre the effect did not grow with concentration, which is unusual for anything acting through a receptor ^[19].
• Not binding the obvious targets. Selank displaced neither a dopamine blocker nor an opioid ligand from their sites in a binding assay, at concentrations above 100 and above 40 micromoles per litre. Whatever it does, it does indirectly ^[20].

Two caveats belong with all of this. The first is the concentrations. They are laboratory concentrations, and nothing shows that a nasal dose ever reaches them in a person ^[15], ^[16].

The second is that Selank falls apart quickly. It breaks into a five-part fragment, a three-part fragment and two two-part fragments. One of those, glycine-proline, reproduced almost the same gene-activity pattern in mouse spleen as the whole molecule did. Part of what is credited to Selank may belong to its debris ^[21], ^[22].

What the trials found

Selank has never been tested the way modern medicines are tested. There is no registered study anywhere in the world, no blinded comparison against a dummy treatment with a symptom outcome, and no replication by anyone outside Russia ^[3], ^[4], ^[5], ^[6].

Anxiety symptoms

Unregistered comparison, no dummy treatment The 2008 study enrolled 62 people with generalised anxiety disorder and neurasthenia, giving Selank to 30 and the sedative medazepam to 32. It reports comparable effects on the Hamilton and Zung anxiety scales, plus an extra stimulating quality for Selank. No blinding is described, there was no dummy arm, and the paper is in Russian only ^[4].

Unregistered comparison, no dummy treatment The 2014 study enrolled 60 people with phobic anxiety and somatoform disorders and compared Selank against phenazepam. It reports a marked calming effect lasting a week beyond the last dose. Phenazepam is a sedative approved only in Russia and a few neighbouring states, so the comparison does not translate internationally ^[5].

A comparison against an active drug, without a dummy arm and without a pre-set margin, cannot separate genuine effect from mere non-inferiority. In anxiety, where dummy treatments perform strongly, that is the decisive gap ^[4], ^[5].

Adding Selank to a sedative

Unregistered comparison The most interesting question of the set was asked in 2015. Seventy people with anxiety, hypochondriacal and somatoform disorders received either phenazepam alone, 30 of them, or phenazepam plus Selank, 40 of them. The combination is reported to have worked sooner and to have produced fewer sedative side effects, both during treatment and after stopping ^[6].

The design tests something real, an added benefit on top of active treatment. It still lacks blinding, a dummy arm and registration, and the unequal group sizes of 30 against 40 argue against a proper one-to-one allocation ^[6].

Healthy volunteers

Brain imaging with a dummy condition The cleanest human work is a 2020 scan of 52 healthy people, measured before a dose and again 5 and 20 minutes afterwards, comparing Semax, Selank and a dummy. It found differences in how strongly the right amygdala was coupled to nearby temporal brain regions ^[7].

That is a picture, not a symptom. The participants were well rather than ill, the paper runs to three pages, nothing was registered, and a change in resting brain coupling does not establish an effect on anxiety ^[7].

Immune measurements

Open, uncontrolled A 2008 report combined cell-culture work with 14 days of open use in patients with anxiety and exhaustion. It describes a shift in the balance of immune signalling molecules and suppression of an interleukin-6 gene in cells from depressed patients. No participant count is given, and there was no control group ^[8].

Animal work

Animal data The most repeated finding in the whole field is that the effect depends on the animal. In anxious BALB/c mice Selank was calming and lengthened the survival of an opioid peptide in plasma. In placid C57Bl/6 mice it did neither ^[23].

Animal data In rats put into morphine withdrawal, a single dose lowered the overall withdrawal score by 39.6 per cent and raised the touch threshold ninefold, with p below 0.0001 for spasms, drooping eyelids and posture. Diazepam did somewhat better, at 49.3 per cent and thirteenfold ^[24]. In alcohol withdrawal, Selank removed the anxiety without changing how much the animals drank ^[25].

Animal data Not everything points one way. In a rat model of Parkinson's disease, neither Semax nor Selank changed movement or avoidance learning; Selank only lowered the animals' anxiety ^[26].

What is still unknown

• What it does in a person. No target identified, and no human mechanism study ^[15], ^[17].
• What the body does with it. The label gives an absolute uptake of 92.8 per cent through the nose and a fall in blood levels over 5 to 5.5 minutes, with no publication behind either figure. For a peptide of this size that uptake would be surprisingly high ^[1].
• Whether it is safe over time. No toxicity, genotoxicity, cancer or reproductive study has been published. The longest animal study ran four weeks ^[1], ^[27].
• Whether it does anything clinically. No registered study, and no blinded comparison against a dummy with a symptom outcome ^[3].
• What injection does. The only approved route is nasal. Injectable preparations circulate anyway, with no human data at all ^[9], ^[28].

Side effects and safety

The safety picture is strange: a medicine sold for more than fifteen years sits on top of an almost empty research file.

• Two listed side effects. Allergic reactions, including delayed ones, and an unpleasant taste when the liquid reaches the throat from the nose. Both are entered as frequency not known ^[1].
• Some of the allergy may be the preservative. The drops contain methyl 4-hydroxybenzoate, and the label warns separately that this ingredient can itself cause allergic reactions, including delayed ones ^[1].
• Who must not use it, per the label. People sensitive to any ingredient, women who are pregnant or breastfeeding, and anyone under 18. The stated reason in each case is that no studies were done, not that harm was shown ^[1].
• A blood-thinning effect the label does not mention. In rat clotting measurements Selank shifted every parameter towards slower clotting, and was the strongest of three related peptides tested. Whether this happens in people has never been examined ^[27].
• Immune reactions to the substance itself. The FDA warns that preparations containing selank acetate may pose a risk of immunogenicity for certain routes, because the peptide can clump and carry peptide-related impurities ^[9].
• Almost no toxicology. The only laboratory safety study found is a cell test on mouse embryonic stem cells, where Selank had little effect on growth, survival or differentiation. A cell test is not a toxicology programme ^[29].
• No safety reporting outside Russia. The FDA adverse event database held no Selank report on 6 September 2026. That reflects the absence of an approved product and of any reporting route ^[30].

Two label claims deserve caution. The product information states that Selank causes no dependence or tolerance, and that no overdose has been recorded ^[1]. Both are negative claims of a kind that only systematic withdrawal, misuse and surveillance studies can support, and no such studies exist. Not recorded is not the same as not happening.

Why this page lists no doses

Selank is a licensed medicine in Russia, with official product information and an approved schedule behind it. Where a medicine is approved, dosing belongs to that label and to the pharmacist or doctor who hands it over.

Outside Russia the opposite problem applies. There is no approved product, no pharmacopoeia standard and no verifiable human pharmacokinetic study to reason from. This page therefore gives no doses, strengths, drop counts, treatment lengths or instructions for use, in either direction.

Development and approval status

• 1995 the first paper appears, describing TP-7 as a tuftsin analogue with stronger effects than tuftsin ^[11].
• 2008 the first clinical comparison is published, a year before approval ^[4].
• 2009 Russia registers nasal drops at the end of April, for supply without a prescription ^[1], ^[2].
• 2014 and 2015 two further comparisons appear, both against phenazepam ^[5], ^[6].
• 2020 a brain-scan study in healthy volunteers becomes the only human work with a dummy condition ^[7].
• 2026 the FDA entry, in the table for withdrawn nominations, records missing human safety information as at 22 April ^[9].

Each negative entry was checked on 6 September 2026 against a primary database. Each check was then validated by searching the same source for a substance known to be there ^[31], ^[32], ^[33], ^[34], ^[35], ^[36].

Two limits apply. The Australian entry rests on the Poisons Standard, because the register itself timed out. The British one rests on the electronic medicines compendium rather than on the regulator's own database ^[34], ^[33].

The registration number has since changed. The product information now current sits under ЛП-№(010951)-(РГ-RU), a number format used for authorisations under Eurasian Economic Union rules, last amended on 15 July 2025. The 2009 national registration and this later number describe the same medicine ^[1], ^[2].

One claim in the literature needs marking. A 2008 animal paper states in its introduction that Selank had completed the third phase of clinical testing. No study report, registration or study plan matching that description could be found. It is an assertion from the developers' circle, not a verifiable record ^[37].

What supported the 2009 approval is unknown. Russia keeps its own register of approved clinical trials, but the search interface could not be read on 6 September 2026, returning nothing even for a commonplace medicine ^[3]. The register record itself was read through a mirror of the official export, because the primary system is captcha-protected ^[2].

A grey market exists and is documented. A Belgian control laboratory identified Selank and Semax in two seized, undeclared preparations in 2017 and 2018. It had to build an analytical method afterwards, and the authors noted that these peptides had completed no clinical trials to their knowledge ^[28].

The FDA describes American wellness clinics and online sellers offering Semax alone and as a fixed 50:50 combination with Selank, both as an injection and as a nasal spray ^[38]. A pharmacology review calls Phenibut and Selank poorly studied Russian drugs sold to US consumers as dietary supplements ^[39]. The general legal picture is set out under are peptides legal and FDA-approved peptides.

Anti-doping

Selank is not named on the 2026 prohibited list, and its position there is genuinely unresolved rather than clear. The catch-all clause covers any substance not addressed elsewhere on the list and with no current approval by any governmental regulatory health authority for human therapeutic use. Russia's health ministry has approved Selank, and that approval stands ^[10].

Read on its wording, the clause therefore may not bite. That sets Selank apart from BPC-157, which the same clause names as an example and which no authority anywhere has approved. None of the other sections of the 2026 list covers Selank either ^[10]. Semax raises the identical question for the identical reason.

No public decision settles it. No statement, register entry or sporting judgment on Selank could be found. That is not reassurance. An athlete subject to testing cannot rely on a reading of the text, and the only binding answer comes from their own anti-doping organisation.

The NCAA does not name Selank either, while stating that its list is neither complete nor exhaustive ^[40]. The wider picture is at peptides banned in sport.

Compared with related peptides

The useful comparison here is with Semax, because the two are constantly conflated. They share the stabilising Pro-Gly-Pro tail, a Moscow origin and a Russian nasal-drop licence, and nothing else. Their active cores come from unrelated molecules: an antibody fragment for Selank, a stress hormone for Semax ^[15].

The comparison with tuftsin makes the opposite point. Selank contains tuftsin, so it is tempting to treat the two as interchangeable. The very first study of the pair found the extended molecule worked more strongly than tuftsin did, which means the tail changes the behaviour and not only the durability ^[11].

Regulators have also treated the two Russian peptides differently. Semax went before an FDA advisory committee in July 2026; Selank was not on that agenda at all, and its own nomination had been withdrawn earlier ^[9], ^[38].

Common misconceptions

• "Selank and Semax are the same thing." Two substances with two different parents. Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, from the immune peptide tuftsin. Semax is Met-Glu-His-Phe-Pro-Gly-Pro, from a fragment of ACTH. Only the tail is shared, and regulators handle them separately ^[15], ^[38].
• "Selank is just tuftsin." It contains tuftsin and is not tuftsin. Adding Pro-Gly-Pro produced a molecule that outperformed tuftsin in the earliest head-to-head study, so the change is not cosmetic ^[11].
• "Over the counter means it has been checked and found safe." The Russian label carries two side effects, both without a frequency, and rules out pregnancy, breastfeeding and under-18s because no studies were done. Meanwhile animal work shows a blood-thinning effect the label never mentions ^[1], ^[27].
• "There are clinical trials of Selank running." There are none registered. The entries that searches return are text coincidences, mostly brain-stimulation trials in which TP7 and TP8 name electrode positions on the scalp rather than the peptide code TP-7 ^[3].
• "N-acetyl Selank amidate is an improved version." No record exists in PubChem under that name, and none of the 77 genuine Selank papers describes an acetylated or amidated variant. The Russian medicine contains the plain heptapeptide as a diacetate salt ^[41], ^[1].
• "The Russian approval proves it works." It proves a regulator accepted a dossier. At the end of April 2009 exactly one clinical paper existed, in 62 people, with no dummy arm and no blinding; the other two appeared in 2014 and 2015 ^[2], ^[4], ^[5], ^[6].
• "Not on the prohibited list means allowed in sport." Not named is not the same as permitted, and here the question is open in both directions. The catch-all clause may not apply, but nobody has ruled on it ^[10].

Frequently asked questions

Is Selank an approved medicine?

In Russia, yes, and unusually it is sold there without a prescription. The state drug register carries nasal drops under registration number ЛСР-003338/09, entered at the end of April 2009. Nowhere else is Selank approved. There is no licence in the United States, the European Union, Germany, the United Kingdom, Australia, Canada or Switzerland, and no pharmacopoeia anywhere carries a quality standard for it.

What do the human studies of Selank actually show?

Much less than the reputation suggests. Five studies exist, covering roughly 250 people between them. Four compared Selank against a Russian sedative rather than against a dummy treatment, and none of the five describes any blinding. The one study with a dummy condition scanned the brains of 52 healthy volunteers and measured no symptom at all. Not one of the five appears in any public trials register.

How does Selank work?

Nobody has shown how it works in a person. Two laboratory ideas dominate. Selank slows the enzymes that break down the body's own opioid peptides, and it appears to nudge the GABA system, the brain's main calming signal. Both findings come from test tubes, membrane preparations and animals, almost all from the same Moscow research groups that created the molecule.

Is Selank the same as Semax or as tuftsin?

No, all three are different. Selank contains tuftsin but is not tuftsin: it is that four-part immune peptide with a three-part tail bolted on, and the tail changes what the molecule does. Semax is a different heptapeptide built from a fragment of the stress hormone ACTH. Selank and Semax share only that same stabilising tail, plus a common origin in Soviet-era Moscow laboratories.

Why does this page not list Selank doses?

Because Selank is a licensed medicine in one country, with official product information and an approved schedule behind it. Where a medicine is approved, dosing belongs to that label and to a doctor or pharmacist, not to a reference page. Everywhere else there is no approved product and no verifiable human pharmacokinetic study to base anything on. Both reasons point the same way.

Is Selank banned in sport?

The honest answer is that it is unresolved, and Selank differs here from most peptides in this register. It is not named on the 2026 prohibited list. The catch-all clause covers substances with no current approval from any government health authority, and the Russian approval is current, so on the wording that clause may not bite. No public ruling settles the point. Anyone tested needs a binding answer from their own anti-doping organisation.

What are the known side effects of Selank?

The Russian product information names two: allergic reactions, including delayed ones, and an unpleasant taste when the liquid runs from the nose into the throat. Both carry the entry frequency not known. For a medicine on sale since 2009 that is a remarkably thin list, and it reflects missing data rather than demonstrated harmlessness. Animal work also found a blood-thinning effect that the label does not mention.

Are there registered clinical trials of Selank?

None. A query of ClinicalTrials.gov on 6 September 2026 using five different search strategies returned no genuine Selank study at all. The entries that a search throws up are text coincidences: in brain-stimulation trials, TP7 and TP8 are electrode positions on the scalp, not the peptide code TP-7. The Russian register of approved trials could not be read, so what supported the 2009 approval remains unknown.

Does the Russian approval prove that Selank works?

No, it records that a regulator accepted a dossier. When the approval was granted at the end of April 2009, exactly one clinical paper had been published, in 62 people, with no dummy treatment and no blinding. The other two clinical studies appeared five and six years afterwards. The approval is a hard fact about legal status, not a verdict on evidence.

Is N-acetyl Selank amidate a stronger form of Selank?

There is nothing published to check. Three PubChem queries for that name on 6 September 2026 returned no record, and none of the 77 genuine Selank papers describes an acetylated or amidated version. The name describes a molecule blocked at both ends, a common trick for protecting peptides from enzymes. The Russian medicine does not contain it.

Cite this page

The facts on this page were checked on 6 September 2026, and the registers behind the status table were queried on that same day. Two things could move: the Russian registration is being carried over into the Eurasian system, and the anti-doping question has never been ruled on. The version and the date therefore matter as much as the text.

myPeptides Research & Editing. (2026). Selank: what the studies show, status and safety. Version 1.0, 6 September 2026. myPeptides Peptide Register. Retrieved from https://mypep.app/peptides/selank

How pages in this register are compiled and graded is described under methodology; the full register is at peptides.

Last verified: 6 September 2026. Next review: on any change to the Russian registration, on any FDA action concerning the substance, or on any clarification of its anti-doping status.