Cognitive
Semax
Decades of use in Russia for focus, mood and stroke recovery — and almost no independent research anywhere else. That gap makes it hard to say with any confidence how well it works or how safe it is outside the country it came from.
Cognitive/nootropic with real clinical history in Russia, minimal Western trial data.
How well studied
Tier Guide: A = Well studied, B = Some good studies, C = Early evidence & D = Barely studied
Tested in people, but in smaller or fewer studies. A decent picture, just less certain.
How it works
Thought to support how brain cells grow and connect in areas tied to focus and memory, though the exact process still isn't fully mapped.
A synthetic fragment thought to support neurotrophic signalling pathways linked to focus and mood.
Reported benefits
- Reported improvements in focus and mood
- Mild nootropic effect described in available research
Who it's typically used for
Timeline to results
Dosage
No established UK/Western clinical dose — Russian clinical protocols exist but haven't been independently validated.
Side effects
- Nasal irritation (intranasal route)reported
- Headachereported
- Anxiety/overstimulationreported at higher doses
Getting it in the UK
No UK doctor can prescribe this at all. It's sold online labelled 'not for human use' — nobody is checking what's actually in it, or whether it's safe.
MHRA: the UK government body that checks a medicine is safe and actually works before doctors are allowed to prescribe it.
Content freshness
- Last reviewed
- 11 Aug 2026
- Regulatory status last checked
- 11 Aug 2026