Selank
Tuftsin-derived anxiolytic heptapeptide
Tuftsin-derived heptapeptide studied intranasally for anxiety and stress-related effects in small human trials, without FDA approval or a modern large clinical evidence base.
Reference dose
250–500 mcg daily
Source-specific educational reference, not an individualized recommendation.
Reference schedule
Daily · 2–4 weeks
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Profiles include evidence, formats, units, source-specific reference amounts and, where relevant, device details. If any of those terms are unfamiliar, do not guess your way through them. Start with a Personalised Guide and we will put the foundations in the right order for you.
At a glance
Length
7 amino acids
A synthetic tuftsin-derived peptide: TKPRPGP.
Human evidence
Small anxiety studies
Comparative trials exist but are limited in size and replication.
U.S. status
Not FDA approved
No approved anxiety or cognitive indication.
Main clinical theme
Anxiety
The strongest direct human literature is anxiolytic rather than broad nootropic use.
What it is
Selank is a synthetic seven-amino-acid analogue derived from tuftsin, a naturally occurring immunomodulatory peptide fragment.
It is most commonly discussed as an anxiolytic/nootropic peptide and has been studied intranasally in small clinical and mechanistic studies.
Research focus
How it works
Selank is a synthetic heptapeptide derived from the immunomodulatory peptide tuftsin. Research has explored anxiolytic effects, enkephalin metabolism, gene expression and brain-network connectivity, but the clinical evidence remains relatively small and region-specific.
Important context
Selank should not be labelled purely preclinical because published human anxiety studies exist. At the same time, those studies are small, largely from a limited research network and do not provide the depth of evidence expected for an FDA-approved anxiety treatment.
What it is studied for
Anxiety research examines symptom reduction and potential alternatives or adjuncts to conventional anxiolytic drugs.
Neurochemical research explores enkephalin metabolism, GABA-related signalling and expression of genes involved in neurotransmission.
Cognitive and stress research often extends from these mechanisms, although the direct clinical evidence for broad cognitive enhancement is much weaker than the anxiety literature.
More contextA human signal exists, but replication is limitedSee the deeper context, evidence details and practical distinctions behind this profile.
A 2008 randomized comparative study included 62 patients with generalized anxiety disorder or neurasthenia and compared Selank with medazepam. A 2014 comparative study evaluated Selank and phenazepam-related treatment strategies in 60 patients with anxiety-spectrum disorders.
Small healthy-volunteer neuroimaging work has also reported acute changes in functional connectivity after Selank, but mechanistic imaging findings are not equivalent to demonstrated clinical effectiveness.
- Human clinical literature is predominantly intranasal and relatively small.
- There is no FDA-approved Selank product, dose or anxiety indication.
- FDA identifies compounded selank acetate as potentially posing immunogenicity risk from aggregation or peptide impurities and states that important human safety information is lacking.
- Online claims involving cognition, ADHD, depression, immune function or broad stress resilience often extend beyond the strongest direct human evidence.
Why people are interested
What makes Selank worth researching.
Limited human comparative studies
Anxiety symptoms
Small comparative human studies reported anxiolytic effects in generalized anxiety and related disorders, including comparisons with benzodiazepine-type drugs.
Limited human data
Tolerability signal
The published small studies described relatively good short-term tolerability, but they are insufficient to define a complete modern safety profile.
Human mechanistic study
Brain connectivity
A small healthy-volunteer fMRI study found acute connectivity changes involving the amygdala and temporal regions after Selank.
Preclinical / mechanistic
Mechanistic research
Laboratory work explores enkephalin-degrading enzymes, gene expression and GABA-related pathways, but proposed mechanisms remain broader than the clinical evidence.
Evidence
Where the evidence is strongest, and what kind of evidence it is.
Human · randomized comparative · n=62
2008 anxiety study
Thirty patients received Selank and 32 received medazepam in a study of generalized anxiety disorder and neurasthenia; the authors reported similar anxiolytic effects.
Human · comparative · n=60
2014 comparative study
A later study reported anxiolytic effects and favorable tolerability compared with phenazepam-based treatment in anxiety-spectrum disorders.
Human · small mechanistic
Healthy-volunteer imaging
Resting-state fMRI work reported acute changes in functional connectivity after Selank or Semax compared with placebo.
Regulatory safety concern
FDA safety position
FDA states that compounded selank acetate may pose immunogenicity risks and that important information about human safety is lacking.
Human research
A 2008 randomized comparative study of 62 patients reported similar anxiolytic effects for Selank and medazepam in generalized anxiety disorder and neurasthenia.
A 2014 comparative study in 60 patients with anxiety-spectrum disorders also reported anxiolytic effects and favorable tolerability.
A 2020 small healthy-volunteer fMRI study found acute functional-connectivity effects after Selank, but imaging changes do not establish clinical anxiety or cognitive benefit.
Preclinical research
Laboratory studies show inhibition of enkephalin-degrading enzymes and effects on neurotransmitter-related gene expression.
Animal work has explored anxiety behavior, stress responses, memory and GABAergic mechanisms.
These mechanistic findings remain hypotheses for clinical action rather than fully validated human mechanisms.
Reference dosing
Reference amount, schedule and conversion.
A reference amount is only useful when you know the formulation, concentration and delivery device it belongs to. Do not transfer a vial amount into a pen, a pen click count into another pen, or a syringe-unit number into a different concentration.
01
Identify the format
Vial, reusable cartridge pen, prefilled multi-dose pen or single-dose autoinjector.
02
Confirm concentration
Know the total peptide amount and liquid volume or the manufacturer/vendor concentration.
03
Understand the units
Keep mg/mcg, mL and syringe units or device clicks separate.
04
Then use the reference
Only convert a known reference amount with the calculator that matches the actual device.
Source-specific reference
250–500 mcg daily
Daily · 2–4 weeks
The 250–500 mcg daily range is a Pep Report research reference. Published intranasal studies use study-specific formulations and regimens.
Calculator connection
This profile does not currently use a vial or pen calculator. Follow the formulation-specific information shown for the product or reference you are using.
The strongest human literature is intranasal rather than vial-based injection research. The generic vial calculator is disabled to avoid implying that a subcutaneous Selank protocol has been clinically validated.
Storage
Start with the format. Then verify the exact product.
Rule of thumb, not a product instruction
Storage belongs to the exact formulation. Generic advice can orient you, but the label, pharmacy directions or formulation-specific stability data should determine the final temperature and usable-life limits.
Pens
Treat a pen as a finished drug-device product: protect it from unnecessary heat and light, do not freeze unless the exact label explicitly permits it, and use that device's own unopened and in-use storage window.
Vials
Treat dry and reconstituted vials as different stability states. Refrigeration after mixing is common for some formulations but is not a universal peptide rule.
Product-specific notes
There is no FDA-approved Selank product label establishing standardized U.S. storage or device requirements.
Intranasal formulations can differ in concentration, excipients and delivery-device performance.
Practical reference
Formats
Intranasal preparations in published human literature
Research preparations
Reconstitution & units
The strongest human evidence is associated with intranasal use rather than subcutaneous injection.
This profile therefore does not provide generic injection-reconstitution instructions.
Study regimens vary and should not be collapsed into one universal microgram target.
The generic vial calculator is disabled because it could imply a validated injectable Selank protocol that the human evidence does not establish.
Safety, status & open questionsOpen the practical cautionsSelank has limited published human anxiety research, but it is not an FDA-approved anxiolytic or cognitive enhancer. Its evidence base is substantially less mature than established anxiety treatments.
Open questions
The main clinical studies are relatively small and come from a limited research ecosystem, with little large independent replication.
There is no FDA-approved dose, product or indication.
Long-term safety, pharmacokinetics and immunogenicity are not well characterized in modern large studies.
Claims for ADHD, depression, cognitive enhancement or immune optimization are less directly supported than the anxiety-focused human literature.
Regulatory notes
Selank is not FDA approved in the United States.
FDA identifies compounded selank acetate as potentially presenting immunogenicity concerns due to aggregation and peptide-related impurities.
FDA states that important human safety information for compounded selank acetate is lacking.
Practical notes
The published human studies are too small to define uncommon or long-term adverse effects reliably.
FDA flags potential immunogenicity from aggregation and peptide-related impurities in compounded selank acetate.
Unapproved intranasal or injectable products can add formulation, identity, purity and concentration uncertainty.
Concomitant psychiatric medications and underlying anxiety disorders create clinical considerations that cannot be addressed by peptide-dose arithmetic alone.
Common mistakes
Calling Selank purely preclinical despite small human anxiety studies.
Treating small regional comparative studies as equivalent to a large independent modern anxiety-drug programme.
Using mechanistic GABA/enkephalin findings as proof of broad nootropic benefit.
Assuming intranasal research validates injected Selank.
Presenting a single online microgram range as an established universal clinical dose.
Common questions
Does Selank have human evidence?
Yes. Small comparative anxiety studies and mechanistic neuroimaging work exist, but the evidence base is limited and much less robust than for established approved anxiolytics.
Is Selank FDA approved?
No. There is no FDA-approved Selank product or anxiety indication.
Is Selank proven as a cognitive enhancer?
No. Mechanistic and imaging studies are interesting, but the strongest direct human clinical literature is anxiety-focused rather than proof of broad cognitive enhancement.
Why is there no vial calculator?
Because the better-described human route is intranasal and there is no validated injectable dosing protocol that a generic vial calculator should imply.
Related peptides & blends
References
Selank vs medazepam in generalized anxiety disorder and neurasthenia
PubMed · 2008
Selank vs phenazepam in anxiety-spectrum disorders
PubMed · 2014
Selank and Semax functional-connectivity study
PubMed · 2020
FDA — potential safety risks for compounded selank acetate
U.S. FDA · 2026
Semax and Selank effects on human-serum enkephalin-degrading enzymes
PubMed · 2001