What Is Botox? A Clinician's Explanation
Botulinum toxin is one of the most studied molecules in medicine — here is what it actually does at the neuromuscular junction, and what that means clinically.
18 June 2026 · 6 min read
The mechanism, simply
Botulinum toxin type A cleaves SNAP-25, a protein required for acetylcholine vesicles to fuse with the presynaptic membrane. Without acetylcholine release, the muscle fibre cannot contract.
The effect is temporary because the nerve terminal sprouts new endings and the original junction recovers, typically over three to four months.
What it treats
Cosmetically, toxin softens dynamic lines caused by repeated muscle movement: glabellar frown lines, forehead lines and crow's feet are the licensed core.
Medically it is used for hyperhidrosis, bruxism, migraine, blepharospasm and spasticity — a reminder that this is a pharmaceutical intervention, not a beauty product.
Why training matters
Dose, dilution, depth and muscle selection determine whether a result looks refreshed or frozen. Anatomy is the difference between a predictable outcome and a heavy brow.
In the UK, botulinum toxin is a prescription-only medicine and must be prescribed following a face-to-face consultation by an appropriate prescriber.