Selank

• Week 1-2: Some report calmer days within 1-2 weeks
• Week 2-4: Eased anxiety in one trial; round ends after week 4
• Week 4-8: Break: see how you feel off it
• Week 8-12: Optional second 4-week round
• Side effects: Usually mild; stop for allergy, odd bleeding, or worse mood

More on each stage

Week 1-2

The Russian label's standard course is 14 days. Community sources say calmer, less anxious days often show up within the first 1-2 weeks, and some feel it within hours. A mild headache in the first day or two is sometimes reported.

Week 2-4

In a Russian trial of people with anxiety, Selank calmed anxiety about as well as the benzodiazepine medazepam, and also eased tiredness. Community users say focus benefits build over 4-6 weeks. The store round ends after week 4.

Week 4-8

Weeks 5-8 are your 4-week break. In one Russian trial, the calming effect lasted about a week after the last dose. Notice how you feel off it; that tells you whether it was helping.

Week 8-12

Weeks 9-12 can be a second 4-week round, on the same 5-days-on, 2-days-off schedule.

Side effects

Usually mild: redness where you inject, a brief headache, or feeling wired if dosed late. Stop and get help for any sign of an allergic reaction or unusual bleeding or bruising.

Based on what people report in the community sources below. Results vary, and many responses are anecdotal.

• Less anxiety

  Clinical trial

  In a Russian trial of 62 people with generalized anxiety or nervous exhaustion, Selank calmed anxiety about as well as the benzodiazepine medazepam. A second trial of 60 people with anxiety disorders found a clear calming effect that lasted a week after the last dose.34

• Calm without feeling sleepy

  Clinical trial

  In the anxiety trial, Selank also eased tiredness and had a mild stimulating effect, unlike medazepam. The Russian label says it does not cause dependence and does not affect driving.31

• Fewer side effects from a prescribed calming drug

  Clinical trial

  In 70 people with anxiety disorders, adding Selank to the benzodiazepine phenazepam made it work sooner and reduced its sleepiness, memory and focus problems. Only use it this way with your doctor's approval.5

• Immune balance

  Human study

  In people with anxiety who took Selank for 14 days, blood levels of immune signalling proteins (cytokines) shifted. What this means for health is not known.6

• Memory protection in animals

  Animal/lab study

  In rats, Selank changed levels of BDNF, a brain growth signal, and prevented memory problems caused by long-term alcohol use. It also improved object memory in rats not given alcohol.1615

• Calm, clear focus

  Community report

  Users report calmer days within 1-2 weeks and clearer focus over 4-6 weeks, and Semax is their most popular partner.23

What it has been studied for

• Generalized anxiety and nervous exhaustion (62 people, compared with the benzodiazepine medazepam)3Clinical trial
• Anxiety and body-symptom disorders (60 people, compared with the benzodiazepine phenazepam)4Clinical trial
• Add-on to phenazepam to speed it up and reduce its side effects (70 people)5Clinical trial
• Immune signalling in people with anxiety6Human study
• Brain connections linked to anxiety, seen on brain scans of 52 healthy people7Human study
• Anxiety in rats, alone and with diazepam. Under chronic stress, Selank plus diazepam worked best13Animal/lab study
• Anxiety in mice, nose drops vs belly-cavity injection (calming effect seen in the more anxious mouse strain)14Animal/lab study
• Memory loss linked to long-term alcohol use15Animal/lab study
• Flu infection and stomach ulcers1819Animal/lab study

Selank is a lab-made chain of 7 building blocks (amino acids). It starts from tuftsin, a small immune peptide your body makes, with 3 extra building blocks added to the end. Your brain's main calming messenger is called GABA. Lab studies suggest Selank helps GABA work better, much as anti-anxiety drugs do, but in a different way. It also slows the breakdown of the body's own calming, pain-easing peptides. Its level in the blood drops within minutes, but the calming effect lasts much longer.

Peak

Not established for under-the-skin shots in humans. After nose drops, the Russian label says it shows up in the blood within 30 seconds.

Half-life

Not established in humans as a formal number. After nose drops, the Russian label says blood levels fall steadily over about 5 to 5.5 minutes. Enzymes in the blood cut it into smaller pieces.

Cleared

Gone from the blood within minutes after nose drops. Neither Selank nor its breakdown pieces show up in 24-hour urine, because tissue enzymes break it down. The effect outlasts the drug: in one trial, the calming effect lasted about a week after the last dose.

Half-life is how long it takes the body to remove half of a dose.184

Once or twice a day. Morning, plus early afternoon if you take a second dose. Avoid evening shots, because Selank can feel mildly stimulating. 5 days on, 2 days off each week (for example, Monday to Friday). Units are for a 30 mg vial mixed with 2 mL water (15 mg per mL).

• Lower end · starter anxiolytic dose

  500 mcg subcutaneously, 2-3 mornings per week

  A starter subq dose some begin at to gauge anxiolytic response before stepping up to the standard 1 mg, still cycled 8 weeks on / 8 off.25

• Most common · community standard

  1 mg subcutaneously, 2-3 mornings per week

  The standard community subq protocol — reconstituted from a research vial, injected in the morning, cycled 8 weeks on / 8 weeks off for anxiety reduction without sedation.25

• Higher end · acute-anxiolysis daily

  2 mg subcutaneously once daily

  An acute-anxiolysis daily subq protocol a minority run during high-stress stretches — offset by mild stimulating effects if dosed late, so the community keeps it mornings.25

• Under-the-skin protocol (not tested in trials)

  250-500 mcg once a day, 5 days on and 2 days off, for 4-6 weeks. The store dose (350 mcg, 5 on and 2 off, 4 weeks) sits in this range, so you can step up toward 500 mcg if you need more.23

• Nose spray protocol (not tested in trials)

  200-300 mcg, 2-3 times a day, for 4-6 weeks, usually 1 month on and 1 month off. Some go up to 600-900 mcg a day, split into 2-3 doses, for 2-4 weeks.23

• Less frequent, larger shots (not tested in trials)

  500 mcg to 1 mg under the skin, 2-3 mornings a week, 8 weeks on and 8 weeks off. Some use 2 mg once a day for short, high-stress stretches.25

• With Semax (not tested in trials)

  1 mg of each under the skin, in the morning, 2-3 times a week.25

Research protocols

• Russian approved nose drops (0.15%, or 1.5 mg per mL)

  2 drops in each nostril, 3 times a day, for 14 days. The course may be repeated after 1 to 3 weeks. The label does not give the dose in mcg.1

• Human anxiety trials (Russia)

  In one immune sub-study, people took Selank for 14 days.364

• Rat anxiety and stress studies

  300 mcg per kg of body weight in the nose, once a day for 14 days, or as a single dose.1311

• Mouse and rat studies

  300 mcg per kg a day, in the nose or by injection into the belly cavity, for 5 days (mice), or by belly-cavity injection for 7 days (rats).1415

Selank is approved in Russia as an anxiolytic but not by the FDA or EMA. The subcutaneous route biohackers use has not been studied in clinical settings. Self-reported anxiety reduction is highly placebo-susceptible.

Dosing guidance built from the cited research and community reports. It is not a prescription.

1. 1
2. 2
3. 3
4. 4
5. 5
6. 6
7. 7
8. 8

On: 4 weeks Break: 4 weeks

A full course at the store pace takes 1 vial. A mixed vial keeps for up to 90 days.

Why the break helps

No study has tested whether breaks help with Selank. The Russian drug label uses short courses with breaks: 14 days of nose drops, repeated after 1 to 3 weeks if needed. Community users most often run 4 weeks on and 4 weeks off. The label says Selank does not cause dependence, and rats showed no tolerance after 14 days, so the break is not about withdrawal. It limits nonstop use of a substance with no long-term human safety data, and lets you check how you feel without it.

Common

• Redness, itching, or a small bump where you injected

  What to do Rotate sites and use a fresh syringe every time. If redness spreads or gets hot and painful, treat it as an infection (see below).

• Mild headache in the first day or two (reported by users)

  What to do Drink water and give it a few days. If it lasts, drop to 250 mcg (the 1.5-unit mark gives 225 mcg) or stop.

• Feeling wired or having trouble sleeping. Selank had a mild stimulating effect in the anxiety trial.

  What to do Take it in the morning only, and skip the afternoon dose.

• Mild tiredness or light-headedness, mostly at higher doses (reported by users)

  What to do Drop to 250 mcg (the 1.5-unit mark gives 225 mcg). Do not drive if you feel drowsy.

Stop and get help

• Allergic reaction: hives, swelling of the face, lips, or throat, trouble breathing, or feeling faint. The Russian label lists allergic reactions, including delayed ones, and the FDA says compounded Selank may trigger an immune reaction.

  What to do Stop Selank and call 911 (or your local emergency number) right away.

• Unusual bruising or bleeding, such as nosebleeds or bleeding gums. Selank slowed blood clotting in a lab test.

  What to do Stop Selank and talk to a doctor soon. Get urgent care for heavy bleeding.

• Anxiety or low mood that gets worse, or any thoughts of harming yourself

  What to do Stop Selank and contact your doctor. In the US, call or text 988 for urgent support.

• Infection at the injection site: redness that spreads, heat, pus, red streaks, or fever

  What to do Stop injecting and see a doctor the same day.

Do not use if

• You are pregnant or breastfeeding: the Russian label forbids it because it has not been studied.
• You are under 18: the label does not allow it.
• You have a bleeding disorder or take blood thinners, unless your doctor agrees.
• You have had an allergic reaction to Selank or similar peptides.
• You take a prescribed anxiety or sleep medicine, unless your doctor agrees. Never stop a prescribed medicine to switch to Selank.

Sources224

Storage

Keep it

Keep the mixed vial in the fridge (2-8 °C / 36-46 °F), away from heat and light. Do not freeze it, and never leave it in a hot car.

How long

Use within 90 days of mixing. A mixed vial kept in the fridge holds its strength for 60-90 days, then slowly starts to lose potency. Wipe the rubber top with an alcohol swab before every draw.

Drawing your dose

Syringe: a 0.3 mL (30-unit) U-100 insulin syringe with half-unit marks, so small doses are easy to read.

1. With this mix, every 1 unit line on a U-100 insulin syringe holds 150 mcg. Draw to the 2.5-unit mark for 375 mcg, the closest mark to 350 mcg. For 250 mcg, the closest mark is 1.5 units (225 mcg); for 500 mcg, it is 3.5 units (525 mcg).
2. Hold the syringe at eye level, flick out air bubbles, and push the plunger back to the exact line.
3. Pinch a fold of skin, insert the needle at 45 to 90 degrees, push slowly, and wait a few seconds before pulling out.
4. Take it in the morning. If you use a second dose, take it by early afternoon so it does not keep you up.
5. Use a new sterile syringe every time and never share one.

• Semax

  Semax is studied for learning and memory, while Selank is studied for calm. Semax raised BDNF, a brain growth signal, in rats, and a brain-scan study in healthy people found each peptide changed anxiety-linked brain connections in its own way. It is the most popular community stack and the store's Clarity pair. They have not been tested together as a treatment.22723

• DSIP

  Some users take Selank for daytime calm and DSIP for sleep. This is a niche community stack. The pair has not been tested together.23

Interactions

• Benzodiazepines (for example diazepam, alprazolam, lorazepam, clonazepam)

  Selank strengthened diazepam's calming effect in stressed rats and made phenazepam work sooner in people. In lab tests on brain cell membranes, Selank changed how GABA binds to its receptors and blocked diazepam's effect on that binding. The combined effect on you is hard to predict.

  What to do Do not add Selank, or change your benzodiazepine dose, without your doctor's approval.

• Blood thinners or anti-platelet medicines (warfarin, apixaban, clopidogrel, daily aspirin)

  Selank slowed blood clotting in a lab test, so bleeding risk could add up. This has not been studied in people.

  What to do Ask your doctor first, and watch for unusual bruising or bleeding.

• Antidepressants, antipsychotics, and other psychiatric medicines

  The Russian label allows Selank alongside these medicines, but in a cell study it added to the antipsychotic olanzapine's effects on gene activity. Injected Selank has not been studied with them.

  What to do Tell the doctor who prescribes them before you start.

• Alcohol

  The Russian label found no interaction with alcohol, but both act on the brain's calming system.

  What to do Keep drinking light, and do not drive if you feel drowsy.

Videos

• Selank Deep Dive: Anxiety, Cognition, Immune SystemQuinn Stillson MD

Sources

1. 1Selank 0.15% nasal drops, Russian prescribing information (RLS drug register, in Russian, updated July 2025)Drug label
2. 2FDA: Certain bulk drug substances for compounding that may present significant safety risks (Selank acetate)Reference
3. 3Zozulia et al., Zh Nevrol Psikhiatr 2008 (Selank vs medazepam, 62 people with anxiety; in Russian)Clinical trial
4. 4Medvedev et al., Zh Nevrol Psikhiatr 2014 (Selank vs phenazepam, 60 people; in Russian)Clinical trial
5. 5Medvedev et al., Zh Nevrol Psikhiatr 2015 (Selank added to phenazepam, 70 people; in Russian)Clinical trial
6. 6Uchakina et al., Zh Nevrol Psikhiatr 2008 (immune effects in people with anxiety; in Russian)Study
7. 7Panikratova et al., Dokl Biol Sci 2020 (Selank and Semax brain scans, 52 healthy people)Study
8. 8Zolotarev et al., Bioorg Khim 2006 (how Selank breaks down in blood and reaches the brain; in Russian)Study
9. 9Zozulya et al., Bull Exp Biol Med 2001 (Selank slows enkephalin breakdown)Study
10. 10Vyunova et al., Protein Pept Lett 2018 (Selank and GABA receptor binding)Study
11. 11Volkova et al., Front Pharmacol 2016 (GABA-related genes in rat brain)Study
12. 12Filatova et al., Front Pharmacol 2017 (Selank with GABA and olanzapine in human nerve cells)Study
13. 13Kasian et al., Behav Neurol 2017 (Selank with diazepam in stressed rats)Study
14. 14Vasil'eva et al., Eksp Klin Farmakol 2016 (nose vs injection in mice; in Russian)Study
15. 15Kolik et al., Bull Exp Biol Med 2019 (memory and BDNF in rats on alcohol)Study
16. 16Inozemtseva et al., Dokl Biol Sci 2008 (Selank and BDNF in rat hippocampus)Study
17. 17Kolomin et al., Mol Immunol 2014 (immune genes in mouse spleen)Study
18. 18Ershov et al., Vopr Virusol 2009 (Selank against flu in cells and mice; in Russian)Study
19. 19Pavlov et al., Bull Exp Biol Med 2007 (stomach ulcers in rats)Study
20. 20Ashmarin et al., Bioorg Khim 2008 (where Selank goes in rat organs by route; in Russian)Study
21. 21Rogozinskaya and Lyapina, Bull Exp Biol Med 2017 (Selank slows blood clotting in a lab test)Study
22. 22Dolotov et al., J Neurochem 2006 (Semax raises BDNF in rats)Study
23. 23Peptide Protocol Wiki: Selank community protocols (120 reports)Community
24. 24Peptide Protocol Wiki: Selank side effects and interactionsCommunity
25. 25The Peptide Catalog: Selank dosing guide (subcutaneous protocols, mixing, side effects)Community

Where people discuss it

• r/Nootropics (subreddit)
• Peptide Protocol Wiki — Selank community (120 reports)
• The Peptide Catalog — Selank SubQ protocol

Some peptides, like semaglutide (Ozempic and Wegovy), are FDA-approved medicines. Most of the peptides people research are not. That label sounds like the FDA tested something and turned it down. Usually it means something else: nobody has paid for the studies the FDA needs to see. Here is why.

The FDA doesn’t test drugs. Companies do.

The FDA does not run its own drug tests. A company that wants to sell a new medicine has to test it first, and pay for it. It studies the drug in animals, then in people: first 20 to 100 volunteers, then a few hundred, then up to 3,000. Then it sends all the results to the FDA. FDA scientists review them and decide whether the benefits outweigh the risks.

So approval always starts with a company asking for it. If no company applies, the FDA has nothing to review, however promising the research looks.

Those studies cost about a billion dollars

A study in the medical journal JAMA estimated that bringing one new drug to market costs a typical company about $1.1 billion. That figure includes the money spent on drug ideas that failed along the way, because many drugs that start human testing never make it.

A patent is how a company earns that money back

A patent is a right the government gives an inventor. For up to 20 years from the day the inventor applies, nobody else may make or sell the invention without permission.

For a drug company, that right is what makes the billion-dollar bet worth it. While the patent lasts, the company is the only seller, so it can charge enough to pay back the studies and the failures. When the patent runs out, other companies can sell cheap copies, called generics, and the price drops.

The FDA adds a shorter shield of its own. For 5 years after a brand-new drug is approved, no copycat version can apply for approval. That helps, but it is much shorter than a patent can last.

Why most peptides can’t be patented

To get a patent, an invention has to be new, and it has to be something people made, not something found in nature. Most popular peptides fail one test or both.

They come from nature. Many are copies or small pieces of molecules your body already makes. KPV is a 3-building-block piece of the hormone that tans your skin. BPC-157 is copied from a protein in stomach juice. In 2013 the US Supreme Court ruled that something that exists in nature, like a human gene, cannot be patented just because someone found it and pulled it out.

They aren’t new anymore. Many were first described in research papers decades ago. Scientists were already testing KPV in the 1980s. Once something has been published, it no longer counts as new, so nobody can patent it now, and any patents from back then have long since run out.

Without a patent, a company that paid for the studies would soon face rivals selling the same peptide without having paid for any research. Few companies will spend a billion dollars on a product anyone can copy. So nobody goes first, and the large human studies never happen.

The workaround: change the molecule

Drug companies do make peptide medicines, but they change the peptide first. A changed molecule is a new invention, so it can be patented. Semaglutide is a lab-made version of GLP-1, a gut hormone your body releases after meals, changed so one shot lasts a week. Tesamorelin (Egrifta) is the body’s own growth-hormone signal with a small fatty chain added. Both went through the full studies, and both are FDA-approved.

The natural versions, and the many peptides nobody has changed and patented, stay where they are: studied in labs and animals, used by the biohacking community, and never put through large human trials.

What this means for you

When a peptide is “not FDA-approved,” it usually means no company has paid for the large human studies. It does not mean the FDA tested it and found it harmful.

It also does not mean it is proven safe or proven to work. Without those studies, nobody knows the best dose for sure, or what rare or long-term side effects it may have. And the FDA does not check research peptides for purity or strength the way it checks approved medicines. That is why this page labels every finding by the kind of study behind it, and lists who should not use it.

Sources for this section

1. 1FDA: How drugs are developed and approved (the FDA does not test drugs; companies submit the evidence)
2. 2FDA: The drug development process, step 3: clinical research (study sizes for each phase)
3. 3Wouters, McKee & Luyten, JAMA 2020, corrected 2022: median cost to bring a new drug to market, $1.14 billion
4. 4US patent law, 35 U.S.C. § 154: a patent lasts 20 years from the filing date
5. 5FDA: Frequently asked questions on patents and exclusivity (5-year new chemical entity exclusivity)
6. 6US Supreme Court, Association for Molecular Pathology v. Myriad Genetics (2013): naturally occurring genes cannot be patented