Cognitive · Reference
Selank Side Effects: What Is Reported, What to Report, and Who Should Not Take It
This page is a practical reference: what is reported, what the trials found, what has never been studied, what to report, and who should not take Selank. The wider picture of what Selank is and where it stands with the FDA is in what is Selank.
Treatments mentioned
The side effects most often reported with injectable Selank are injection-site redness, mild soreness and occasional bruising, plus early fatigue or a flat, low-drive feeling in some people and, less often, a sense of being wired. These are usually described as settling. The Russian trials, which used a formal side-effect scale and compared Selank with benzodiazepines, reported no sedation, no memory impairment, no dependence signal and no withdrawal over the study periods. The gaps matter as much as the findings: there is no long-term safety data, no trial of the injection, and no study of Selank alongside SSRIs, SNRIs, stimulants or antipsychotics.
This page is a practical reference: what is reported, what the trials found, what has never been studied, what to report, and who should not take Selank. The wider picture of what Selank is and where it stands with the FDA is in what is Selank.
Selank Side Effects
The short answer
| Side effect | How it is described | What to do |
|---|---|---|
| Injection-site redness, mild soreness, occasional bruising | The commonest complaint | Rotate sites |
| Fatigue or a flat, low-drive feeling | In the first days, usually settling | Tell your care team if it persists |
| Feeling wired | A small number of people, usually settling | Tell your care team if it persists |
| Sedation, memory impairment | Reported as absent in the Russian trials | Report anything like it |
| Dependence or withdrawal | No signal reported in the trials | Tell your care team if anything shifts when you stop |
| A severe or spreading reaction, or difficulty breathing | Rare | Emergency care first (call 911), then your physician |
| A marked change in mood | Not a described effect, but always reportable | Contact your physician promptly |
There are no placebo-controlled rates for Selank side effects, so this page gives descriptions, not percentages. The product it covers:
| Product | What is in it | Price |
|---|---|---|
| Selank | 5 mL multi-dose vial, Selank 2 mg/mL (10 mg Selank per vial) | $229/mo |
The price is all-in: medication, physician review, refill management and shipping, with no membership fee. Pepti is cash-pay and does not bill insurance. Compounded medications are not FDA approved.
Selank Side Effects
Common Selank side effects
Selank is a seven-amino-acid peptide built from tuftsin, a fragment of immunoglobulin G, with a Pro-Gly-Pro tail added to slow its breakdown. It is described around GABA signalling and stress reactivity. Nearly everything people report falls into two groups: the injection itself, and a short adjustment in how they feel during the first days.
At the injection site
Redness, mild soreness and occasional bruising are what gets reported most with the injectable. They are the same reactions seen with most subcutaneous peptides. Rotating sites between the abdomen and thigh, and not using the same spot repeatedly, is the practical answer. Technique is covered in how to inject peptides safely.
Fatigue or a flat feeling
Some people describe fatigue or a flat, low-drive feeling in the first days. It is usually described as settling. Because Selank is described around the stress response, a change in how "switched on" you feel is the kind of effect you would expect to notice, if any.
Feeling wired
A small number of people report the opposite: a sense of being wired. The 2008 Russian trial described Selank as mildly activating, which fits. This is also usually described as settling.
What the trials found was absent
Selank is described as well tolerated in the Russian trials, a stronger statement than for most peptides because those trials used the UKU side-effect scale and compared Selank with the benzodiazepines medazepam and phenazepam:
Study Who What was reported on safety Zozulya and colleagues, 2008 62 patients with generalised anxiety disorder or neurasthenia, Selank vs medazepam Similar anxiolytic effect; Selank described as anti-asthenic and mildly activating Medvedev and colleagues, 2014 60 patients, Selank vs phenazepam Effect persisted about a week after the last dose; no withdrawal described Medvedev and colleagues, 2015 70 patients, phenazepam alone vs phenazepam plus Selank Fewer benzodiazepine side effects in the combination group Across these, the finding reported most consistently is what did not happen: no sedation, no memory impairment, no dependence signal and no withdrawal. Those are reported findings from small studies lasting weeks, using the intranasal product, not a guarantee for an injection used for longer.
Selank Side Effects
When side effects tend to show up
| Point in treatment | What is typical |
|---|---|
| Each injection | Possible redness or soreness at the site |
| The first days | Fatigue or a flat feeling in some people; feeling wired in a few |
| The first weeks | Usually settling; prescribers describe any change in stress as subtle rather than an effect at the time of injection |
| Weekends | Part of the schedule; the 2014 trial reported the effect persisting about a week after the last dose |
| After stopping | No withdrawal or rebound anxiety described in the trials |
These are patterns, not promises. Some people notice nothing at all, which is normal.
Selank Side Effects
What has never been studied
This is the part of the safety picture most pages leave out.
| Gap | Why it matters |
|---|---|
| No placebo-controlled trial | There are no side-effect rates against placebo to compare with |
| No trial of the subcutaneous route | The trials used the intranasal Russian product |
| No long-term data | The trials ran for weeks |
| No independent replication | All of the trials come from the developing institutions and their partners |
| No interaction studies with SSRIs, SNRIs, stimulants or antipsychotics | Nobody knows how Selank behaves alongside them |
| The one combination studied | Selank with the benzodiazepine phenazepam, under supervision |
There is no established interaction list, because the trials that would produce one have not been run. That is why the intake asks for every medication you take, and why a physician reviews it rather than a form.
Selank Side Effects
When to message your care team
Message your care team through your account if:
- Fatigue, a flat feeling or a wired feeling has not settled after the first days.
- An injection-site reaction is getting bigger, more painful or warmer rather than fading.
- You start, stop or change any psychiatric medication, stimulant or sedative.
- Your anxiety is getting worse rather than better.
- Anything shifts when you stop.
- Your label and your syringe seem to disagree. Do not dose until it is sorted.
Do not change your dose yourself in response to a side effect. Your physician sets your directions after reviewing your intake, and any change is printed on the new label.
Selank Side Effects
Serious reactions: what needs urgent care
| Symptom | What it may be | What to do |
|---|---|---|
| Swelling of the face, lips or throat, widespread rash, trouble breathing | A serious allergic reaction | Call 911 or go to an emergency department first |
| A reaction at the site that is severe or spreading | A significant local reaction or infection | Stop and contact your physician the same day |
| A marked change in mood | Needs prompt assessment | Contact your physician promptly; if you feel unsafe, call 911 |
Emergency care comes first for anything involving breathing. Tell your physician afterwards so it is on your record.
Selank Side Effects
Selank alongside other medications
Psychiatric medication
If you take an SSRI, SNRI, benzodiazepine or antipsychotic, or have been diagnosed with panic disorder, bipolar disorder or major depression, that treatment comes first, and Selank is at most an adjunct that your prescriber may or may not agree to. Do not stop or reduce a prescribed psychiatric medication to make room for Selank.
Benzodiazepines
The 2015 trial combined Selank with phenazepam under supervision and reported fewer benzodiazepine side effects. That is one supervised study of 70 patients, not a basis for combining them without your prescriber.
Selank in blends
Selank is also in the SERENITY, ELEVATE and SYNAPSE blends and the Semax + Selank vial. Each blend's other ingredients have their own side-effect profiles, covered in what is the SERENITY blend, what is the ELEVATE blend, what is the SYNAPSE blend and what is Semax + Selank.
Selank Side Effects
Who should not take Selank, or should discuss it first
| Situation | Status |
|---|---|
| Pregnancy or breastfeeding | Not used; safety data is absent |
| Existing psychiatric treatment | Reviewed with the prescriber before adding anything |
| A previous reaction to Selank or an ingredient of the vial | Raise it at intake |
| Tested athletes | Many peptides are prohibited in competition; check the current list for your sport |
| Under 18 | Pepti prescribes to adults only |
Bloodwork is not required for any Pepti treatment. If your physician wants labs for your care, they'll ask through your account.
Selank Side Effects
Selank vs Semax side effects
The two are sibling peptides from the same Russian institute, and their side-effect descriptions differ in a way that matches their direction. Semax is occasionally described as causing restlessness if taken late in the day, or an early headache, and a mouse study reported it increasing amphetamine-induced dopamine release. Selank is more often described as causing early fatigue or a flat feeling. Both are mostly injection-site reactions in practice. The comparison is in Selank vs Semax.
Selank Side Effects
What the evidence shows, honestly
Selank's safety record is better documented than most compounded peptides because its trials used a formal side-effect scale and an active comparator. The consistent finding is the absence of the sedation, memory impairment and dependence associated with benzodiazepines.
The limits: the trials are small, 60 to 70 patients each, all from the groups that developed the molecule, none placebo-controlled, none longer than weeks, none by injection, and none replicated outside Russia. A 2021 review in the Journal of Clinical Pharmacology characterised Selank as poorly studied outside its country of origin.
On regulation: Selank acetate was placed in Category 2 of the FDA's 503A list in 2023 over a generic concern about immunogenicity from aggregation and peptide-related impurities, applied to almost every peptide in that batch, and was removed on 27 September 2024 after the nominator said it had intended to nominate a different substance. That concern is a quality one, which is a reason to care where a compounded peptide comes from. Pepti's lot test results are published at /quality/lab-results.
Selank Side Effects
Where to get Selank prescribed
Selank cannot be bought legitimately without a prescription. Products sold "for research use only" have no accountable pharmacy behind their identity, purity, sterility or concentration. The prescription route:
- Complete a free online intake covering your history, medications and what you want help with.
- A physician licensed in your state reviews it, usually within 24 hours.
- If it is appropriate, a PCAB-accredited, FDA-registered US 503A compounding pharmacy prepares it to that prescription.
- It ships refrigerated with ice packs, with sterile syringes and alcohol prep pads, and your directions printed on the vial.
- Your care team stays reachable for side effects and dose questions. Refills run every 28 days, one vial per fill.
The step-by-step page is how to get Selank prescribed online. The dosing detail is in Selank dosage, and what the research has looked at is in Selank benefits.
References
What this is based on.
References
- Kozlovskaya MM, Kozlovskii II, Val'dman EA et al.. Selank and short peptides of the tuftsin family in the regulation of adaptive behavior in stress · Neurosci Behav Physiol (2003) · PMID 14969422
- Zozulia AA, Neznamov GG, Siuniakov TS et al.. Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia · Zh Nevrol Psikhiatr Im S S Korsakova (2008) · PMID 18454096
- Medvedev VE, Tereshchenko ON, Israelian AIu et al.. A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders · Zh Nevrol Psikhiatr Im S S Korsakova (2014) · PMID 25176261
- Medvedev VE, Tereshchenko ON, Kost NV et al.. Optimization of the treatment of anxiety disorders with selank · Zh Nevrol Psikhiatr Im S S Korsakova (2015) · PMID 26356395
- Uchakina ON, Uchakin PN, Miasoedov NF et al.. Immunomodulatory effects of selank in patients with anxiety-asthenic disorders · Zh Nevrol Psikhiatr Im S S Korsakova (2008) · PMID 18577961
- Zozulya AA, Kost NV, Sokolov OY et al.. The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity · Bull Exp Biol Med (2001) · PMID 11550013
- Vyunova TV, Andreeva L, Shevchenko K, Myasoedov N. Peptide-based Anxiolytics: The Molecular Aspects of Heptapeptide Selank Biological Activity · Protein Pept Lett (2018) · PMID 30255741
- Volkova A, Shadrina M, Kolomin T et al.. Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission · Front Pharmacol (2016) · PMID 26924987
- Filatova E, Kasian A, Kolomin T et al.. GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells · Front Pharmacol (2017) · PMID 28293190
- Inozemtseva LS, Karpenko EA, Dolotov OV et al.. Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus in vivo · Dokl Biol Sci (2008) · PMID 18841804
- Kolik LG, Nadorova AV, Antipova TA et al.. Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats · Bull Exp Biol Med (2019) · PMID 31625062
- Doyno CR, White CM. Sedative-Hypnotic Agents That Impact Gamma-Aminobutyric Acid Receptors: Focus on Flunitrazepam, Gamma-Hydroxybutyric Acid, Phenibut, and Selank · J Clin Pharmacol (2021) · PMID 34396551
Citations are provided for educational purposes. They do not constitute medical advice. Always discuss any peptide protocol with your prescribing physician.
Common questions
Selank Side Effects, answered.
Most commonly injection-site redness, mild soreness or occasional bruising. Some people describe early fatigue or a flat, low-drive feeling, and a few describe feeling wired; both are usually reported as settling.
The Russian trials reported no sedation. Some people describe fatigue in the first days, which usually settles. If it does not, tell your care team.
That is not a described effect, though a few people report feeling wired. If your anxiety is getting worse, message your care team rather than changing the dose.
The trials reported no dependence signal and no withdrawal over the study periods, in contrast to the benzodiazepine comparators. That is a reported finding from small, weeks-long studies.
None were described in the published trials. Tell your physician if anything shifts when you stop.
The trials reported no memory impairment, which was one of the specific things they measured against benzodiazepines.
That combination has not been studied. Existing psychiatric treatment is raised at intake, and your prescriber reviews it before anything is added.
One supervised Russian trial of 70 patients combined Selank with phenazepam and reported fewer benzodiazepine side effects. It is not a reason to combine them without your prescriber.
Unknown. The trials ran for weeks, and there is no long-term human safety data.
For swelling of the face, lips or throat, a widespread rash or trouble breathing, call 911 first. For a marked change in mood, contact your physician promptly, and call 911 if you feel unsafe.
It is described as well tolerated in small Russian trials with a formal side-effect scale. There is no placebo-controlled, long-term or injection-route safety data, and compounded medications are not FDA approved. The free assessment goes to a physician licensed in your state. A consultation does not guarantee a prescription.
Next step
See what a physician recommends for you.
A licensed physician in your state reviews your intake and decides what is appropriate. A consultation does not guarantee a prescription.