Semax / Selank
Semax and Selank blendcognitive blendSemax SelankEvidence
Preclinical
Typical vial
10 mg
Route
2 routes
Status
United States
What it is
Two Russian-developed neuropeptides in one vial, usually 10 mg of each. Both rest on literature that has not been independently replicated in the West.
What is in the vial
| Compound | Per vial | Share |
|---|---|---|
| SemaxACTH-fragment analogue. The attention and recovery half. | 10 mg | 50% |
| SelankTuftsin analogue. The anxiolytic half. | 10 mg | 50% |
The ratio is fixed in the vial. Choosing a dose of one component chooses the dose of all the others — you cannot move one without moving them all.
What the contents cost separately
The same masses this vial holds, bought as individual vials, at the cheapest confirmed listing and at the median across vendors. We do not price blend vials themselves — hold this against whatever you are being quoted.
$22–$80
for 20 mg across 2 compounds
| Compound | In this vial | Separately |
|---|---|---|
| Semax | 10 mg | $10–$39 |
| Selank | 10 mg | $12–$41 |
Buying separately costs more injections and more vials, and buys back the ability to change one dose without changing the others. Prices are read from vendor sites and normalised per milligram; we take no vendor placement. Every listing.
The one nootropic blend that genuinely ships pre-mixed, commonly as a 20 mg vial with 10 mg of each. Semax and Selank are frequently discussed together and are sold together for that reason.
They are not the same kind of compound. Semax is derived from an ACTH fragment and is discussed for attention and recovery; Selank is a modified tuftsin analogue discussed for anxiety. Combining them targets two different things at once, which is a reason to want them separate rather than fixed in one vial.
Both carry the same underlying evidence problem: the human literature is largely Russian, largely from the institutes that developed them, and has not been independently replicated. That is a statement about corroboration rather than about plausibility.
How it works
Two mechanisms arriving together, not studied as a mixture.
Semax is a fragment analogue of ACTH(4-10), discussed in terms of BDNF expression and attention in Russian clinical literature.
Selank is a synthetic analogue of tuftsin, discussed as an anxiolytic without the sedation of benzodiazepines.
Neither mechanism has been established in independently replicated human work.
What it is studied for
Each entry states the evidence behind it. We do not rank indications by effectiveness — for most compounds here, that would be a claim nobody can support.
Attention, mood and stress
Published reviewWhat the combination is sold for.
EvidenceBoth components have Russian clinical literature that has not been independently replicated. The mixture has not been studied at all.
Regulatory status
Last reviewed 25 Aug 2026. Positions in this category change frequently, so we date the line.
Not approved in the United States as a mixture or as either of its parts. Both components are registered medicines in Russia.
Identity and clearance
What the molecule is, and how long a dose stays measurable.
Molecule
- Class
- Pre-mixed blend of two neuropeptides, 1:1 by mass
A 20 mg vial is 10 mg of each.
Dose protocols reported in sources
Displayed for reference only. Every row says where it came from, and a trial protocol and a community convention are not the same kind of information. None of this is fed into the calculator, and none of it is a recommendation.
| Goal | Dose | Frequency | Route | Units, 10 mg vial | Source | Start this protocol |
|---|---|---|---|---|---|---|
| Commonly described community protocol | 300 mcg – 600 mcg | Once or twice daily, in courses of 2 to 4 weeks | NasalTotal blend. At 1:1, 300 mcg of blend delivers 150 mcg of each component. Intranasal is the common route for both components separately. | 15–30 u | Community practice | Start this |
The doses above in syringe units, for the vial you have:
Start this copies a row into a protocol of your own, which you can then edit. Where a source gave a dose range or an ambiguous frequency, those fields arrive empty — we will not pick a number on your behalf.
CheckRows marked community practice describe what people commonly do, drawn from public discussion. They are not derived from any trial and are not evidence that a dose is safe or effective.
Work out what to draw
Pre-filled with a 20 mg vial as a worked example. These are not recommended values — change them to match the vial in front of you.
Draw to 3 units on a 1 mL U-100 syringe. That is 0.03 mL, containing 300 mcg of Semax / Selank.
Check3 units falls between the printed lines on a 1 mL U-100 syringe. Mixing with 4 mL of water instead would put this dose at 6 units.
BioAlmanac performs arithmetic on values you enter. It does not recommend doses, schedules or compounds, and nothing here is medical advice. Confirm every calculation against your vial and syringe before drawing, and speak with a licensed healthcare provider.
Open this calculation in the full calculator
Units, concentration, bacteriostatic water — the glossary defines the vocabulary, and a unit is not a fixed volume.
Safety
Reported effects, the situations that need care, and the ones that mean stop.
Reported effects
- Everything from two compounds at oncePublished review
Unknown
No human study of the mixture. Each component's own adverse-effect profile applies, and they cannot be separated if something goes wrong.
- Injection site reactionsCommunity practice
Commonly reported
- Nasal irritationCommunity practice
Commonly reported
The usual route for both components is intranasal.
When to stop
- Any allergic response: rash, hives, facial swelling or difficulty breathing. Seek urgent care.
- New or worsening anxiety, agitation or sleep disturbance.
- Persistent headache, which is the effect most commonly reported with Semax.
- Nasal pain, bleeding or a sense of obstruction that does not settle between doses.
Interactions and situations that need care
- Pregnancy and breastfeedingAvoid
No safety data for either component, let alone the mixture.
- Wanting to control the dose of one componentUse caution
Two compounds at a fixed ratio means Two doses chosen at once. Running them separately is the only way to dose them separately.
- Taking psychiatric medicationUse caution
Both components are discussed as acting on mood and attention, and neither has been studied alongside psychiatric medicines.
What to expect
What the sources describe over time, and how confident anyone can be about it.
HonestlyThere is no human efficacy data for this compound, so there is no evidence-based timeline to give. Any site publishing a week-by-week schedule of expected effects has invented it.
- No study of the mixture. Both components rest on unreplicated Russian literature.
- They target different things — attention and anxiety — which is an argument for dosing them separately.
- Fixed 1:1 ratio, so you cannot raise one without the other.
- Commonly used intranasally rather than injected.
Storage and combinations
How to keep it, and what it does and does not go with.
Storage and handling
- Freeze-dried powder
- Refrigerated at 2–8 °C, protected from light.
- After mixing
- Refrigerated at 2–8 °C and used within about 30 days. A blend cannot be split. A contaminated vial takes every component with it.
- Long-term, frozen
- Unopened powder is stable at −20 °C or colder.
Checking your vial
Research chemicals carry no manufacturing standard, so what the vial looks like is often the only quality signal available before you use it.
Clear and colourless after reconstitution
Nothing here is coloured. A tinted solution is not this blend.
Cloudiness or visible particles
Discard it.
Vocabulary on this page
- Subcutaneous
- Into the layer of fat beneath the skin rather than into muscle. The route almost every peptide on this site uses.
- Blend
- One vial containing several peptides at a fixed ratio, reconstituted and drawn together.
- Vial
- The small sealed glass container a peptide is sold in, holding a stated mass of freeze-dried powder under a rubber stopper.
- Evidence level
- The category of human evidence behind a compound, from preclinical through to approved. Stated on every profile here as a category, not an adjective.
- Stack
- Several separate compounds run at the same time, each in its own vial and on its own schedule.
- Injection site
- Where on the body an injection is given. Rotating between sites is standard practice for anything given repeatedly.
Questions
- Is this the same as the cognitive stack with Dihexa?
- No. Semax with Selank is a blend that genuinely ships in one vial. A three-way with Dihexa is a stack somebody assembled from separate vials — we could not find it sold pre-mixed.
- Injected or intranasal?
- Both components are commonly used intranasally, and the blend is usually described that way. Some vendors list it for subcutaneous use. The route changes the dose, and neither has been established for the mixture.
References
Everything on this page that came from a source, with the source.
Component evidence for common peptide blends: an assessment of what is known separately
Preclinical peptide literature, 2024 · Assessment of the separate component literatures
Cell culture and rodent models
Every component of the common blends is supported by animal or cell-culture work only. No study has examined any of these combinations as a mixture, so combination evidence is weaker than the single-compound evidence. That is itself preclinical.
Community and vendor practice, unverified
Vendor listings and community protocols, 2026 · Anecdote
Self-selected, unverified
Ratios and doses as vendors sell and users describe them. Ratios vary between sellers, so a blend bought from two vendors is not necessarily the same product.
Semax / Selank compared with
Also compared with Semax, Cerebrolysin, Dihexa, N-Acetyl Semax Amidate, Adamax, Adalank.
Related compounds
Semax
A seven-amino-acid peptide developed in Russia and approved there for stroke and cognitive indications. It holds no approval elsewhere and is used nasally rather than injected.
Cerebrolysin
A pig-brain peptide preparation approved as a medicine in around forty countries. Decades of trials, and systematic reviews that still cannot find a clear benefit.
Dihexa
A small peptide reported as vastly more potent than BDNF at forming new synapses in animals. No human has been studied on it, and the potency is the concern, not the selling point.
N-Acetyl Semax Amidate
Semax with both ends chemically capped so it lasts longer. More potent per milligram in animal work, and no human trial of the modified version exists.
Next
What to do with Semax / Selank
- Keep a record of itTurn a dose and a schedule into a protocol, then log what you actually take. Semax / Selank is filled in for you.
- See what it costsPer-milligram prices read from vendor sites and confirmed by a person, so vial sizes compare.
- Check a combinationWhat our profiles record about Semax / Selank alongside each other compound — including the pairs where nothing is recorded.
Keep this page honest
If something here is wrong, out of date, or missing a source, tell us and we will fix it and say that we did.
This page is educational. It describes what published research reports, not what you should do. Peptides discussed here are largely not approved for human use, and nothing on BioAlmanac is medical advice. No clinician reviews these pages.
Page last updated 25 Aug 2026