Semax: the complete UK guide
One page on the peptide behind FOCUS-01: what it is, what the research measured, how it is dosed, how it compares with Selank and the variants, its legal position in the UK, and where to buy it.
What Semax is
Semax is a short synthetic peptide, seven amino acids long, built from a fragment of the hormone ACTH with a protective tail that stops the body breaking it down in minutes. It was developed at the Institute of Molecular Genetics in Moscow, registered for clinical use in Russia in 1994, and has been studied ever since for attention, memory and learning. It is taken intranasally because, like all peptides, it does not survive digestion. Full guide: what is Semax?
What the research shows
The human evidence rests on a controlled 1996 study of healthy volunteers working eight-hour shifts: after a single intranasal dose of 0.25 to 1 mg, attention and short-term memory improved, most in the most fatigued, and work efficiency stayed higher for 20 to 24 hours [1]. The mechanism, from animal and cell studies, is a rapid rise in BDNF, the growth factor behind learning [2][3][5][6], plus activation of the brain’s own dopamine and serotonin systems without a stimulant effect [4]. Every paper is listed on the research page, with the limitations. Semax benefits, claim by claim and BDNF explained.
Semax nasal spray: dosage and use
One spray per nostril in the morning, 20 to 30 minutes before the work that matters; never more than four sprays in 24 hours. Effects begin at 20 to 30 minutes and one dose covers a working day. Judge it over a week, not a day, because there is no stimulant rush to announce it. Guides: dosage, how long it takes to work, nasal spray technique, storage.
Side effects and safety
Reported effects are infrequent and mild: nasal irritation, occasional headache. No cardiovascular effects, no dependence and no withdrawal have been documented at study doses. Not for under-18s, pregnancy or breastfeeding, and anyone on prescribed medication should speak to their prescriber first. Side effects in full.
Semax vs Selank, and the variants
Selank is the sister peptide from the same institute, built for stress and composure rather than attention; many people use Semax in the morning and Selank later. N-Acetyl Semax Amidate, Adamax and the rest are modifications with no human studies. Semax vs Selank and Semax vs NA-Semax Amidate, Adamax, Noopept and Cerebrolysin.
Semax in the UK: legal position and buying
Semax is neither a controlled substance nor a licensed medicine in the UK; it is sold as a food supplement and is legal to buy, possess and use. Most of what is sold online is research-grade powder in 10 mg or 20 mg vials "not for human use", with no published testing. FOCUS-01 is the alternative: a finished metered spray made in the UK at 99.2% assayed purity, with the certificate published for every lot. Is Semax legal in the UK?, vials vs a metered spray, batch results.
Semax questions
A synthetic seven-amino-acid peptide (Met-Glu-His-Phe-Pro-Gly-Pro) derived from a fragment of ACTH, developed in Russia and studied since the early 1990s for attention, memory and learning. It is taken as a nasal spray.
In a controlled study of healthy adults it improved attention and short-term memory scores across an eight-hour shift, with the effect lasting 20 to 24 hours. In animal work it raises BDNF, the brain’s learning signal, and activates dopamine and serotonin systems without a stimulant effect.
Semax is not a controlled substance in the UK and is not a licensed medicine. It is sold as a food supplement. Possessing and using it is legal. Full detail on our legality page.
No. It contains no caffeine or amphetamine-like compound and does not raise heart rate or blood pressure in the studies. Users describe the effect as quiet rather than wired.
As a nasal spray, one spray per nostril in the morning, 20 to 30 minutes before focused work. Do not exceed four sprays in 24 hours.
About 20 to 30 minutes for the first effects. One dose covers a working day; the human study recorded improvement 20 to 24 hours later.
Dry powder, yes. A finished preserved spray like FOCUS-01 is fine at room temperature while in use, and in the fridge for unopened spares.
The research used single and short-course dosing; daily use for a working month is common and no tolerance has been documented at study doses. Some users take weekends off as a precaution.
FOCUS-01 is a Semax nasal spray made in the UK at 99.2% assayed purity, dispatched next working day, with the batch certificate published. It costs £39 for about forty doses.
Every Semax article
Semax benefits: what it does, and what it doesn't
The four effects with data behind them, the claims that have none, and who gets the most from it.
How long does Semax take to work, and how long does it last?
Onset in 20 to 30 minutes, the peak window, and why one morning dose covers a working day.
Does Semax need to be refrigerated? Storage and shelf life
Powder, home-made solution and a finished spray each need different handling. Here is what lasts and for how long.
Semax 20mg vials vs a metered nasal spray: what the numbers mean
What the milligrams on a research vial mean, how reconstitution maths works, and where DIY sprays go wrong.
Semax vs N-Acetyl Semax Amidate, Adamax, Noopept and Cerebrolysin
The variants and the rivals, each against the original: what exists, what is studied, what is marketing.
Peptide nasal sprays explained: why peptides go up the nose
Why a capsule would not work, how the nasal route reaches the brain, and what a good peptide spray needs.
BDNF: what it is, why it matters for learning, and how to raise it
The brain's growth signal, what raises it (exercise, sleep, Semax) and why there is no BDNF supplement as such.
What Reddit says about Semax: a sober read
Where r/Nootropics experience matches the research, where it goes beyond it, and how to read a thread.
What is Semax? A plain-English guide
Where the peptide came from, what it does in the brain, and what thirty years of research actually measured.
Semax dosage: how much, when, and how long it lasts
The doses used in the studies, how a metered spray maps onto them, timing before focused work, and storage.
Semax side effects and safety: what the research says
What has been reported, what has not, who should avoid it, and why it is not a stimulant.
Semax vs Selank: which one, and can you use both?
Two peptides from the same lab with different jobs. How they differ, and how FOCUS-01 and CALM-02 fit a day.
Is Semax legal in the UK?
The short answer, the longer one, and what it means for buying and using a Semax nasal spray in Britain.