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Neurotoxin — Therapeutic / Cosmetic

Botulinum Toxin Type A

Brand names: Botox (onabotulinumtoxinA), Dysport (abobotulinumtoxinA), Bocouture (incobotulinumtoxinA), Azzalure

A purified neurotoxin from Clostridium botulinum injected to produce localised muscle relaxation, used for therapeutic indications such as focal dystonia, spasticity, hyperhidrosis and chronic migraine, and for facial aesthetic and scar treatment in plastics.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It cleaves SNAP-25, blocking presynaptic release of acetylcholine at the neuromuscular junction and at cholinergic autonomic nerve endings, producing temporary, reversible chemodenervation.

Prescribing in practice

  • Toxin may spread beyond the injection site causing distant muscle weakness, dysphagia and breathing difficulty, so it must be administered only by trained clinicians and units are not interchangeable between brands.
  • Avoid in infection at the proposed injection site and in known hypersensitivity, and use with caution in neuromuscular disorders such as myasthenia gravis.
  • Effects are temporary and wear off over weeks to months, requiring repeat treatment.

Monitoring

Monitor for the intended functional response and for signs of unwanted local or distant muscle weakness after each treatment cycle.

Counselling the patient

  • The effect develops over several days and is temporary, lasting some months.
  • Seek urgent help for swallowing, speaking or breathing difficulty, or generalised weakness.
  • Avoid rubbing the treated area immediately after injection.

Evidence & guidelines

The MHRA highlights that botulinum toxin products are not interchangeable and carry a risk of toxin spread, reflected in product labelling.

Reference: MHRA Botulinum Toxin Guidance; BAPRAS (British Association of Plastic, Reconstructive and Aesthetic Surgeons) Scar Management Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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