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botulinum toxin

Neurotoxin, Inhibitor of ACh release · Antispasmodic

Neurotoxin, Inhibitor of ACh releaseAntispasmodic
CDSCO approved
EXCRETION
not curated
INTERACTIONS
none in our sources
PREGNANCY
not curated

Mechanism

Botulinum toxins bind to cholinergic neurons, enter the cell, and cleave SNARE proteins, thereby inhibiting vesicular release of acetylcholine. The result is flaccid paralysis of skeletal muscle and diminished activity of parasympathetic and sympathetic cholinergic synapses.

Indications

Management of ocular blepharospasm and strabismusManagement of other muscle spasms and dystoniasFacilitate facial muscle relaxationAchalasia (lower esophageal sphincter injection)Cosmetic procedure for wrinklesCervical dystoniaGlabellar lines (moderate to severe)Axillary hyperhidrosis (severe)Chronic migraine prophylaxisOveractive bladderUpper limb spasticity (severe)Urinary incontinence (due to detrusor overactivity associated with a neurologic condition)

Pharmacokinetics

Duration
Inhibition lasts from several weeks to 3–4 months; restoration of function requires nerve sprouting.

Contraindications

  • Units of biological activity for different preparations are not interchangeable
  • Administer with great caution due to extreme toxicity

Side effects

Serious
  • Extremely poisonous (lethal doses roughly 1 ng/kg IM/IV, 10 ng/kg inhaled, 1000 ng/kg ingested)
  • Risk of respiratory paralysis from unexpected spread of the toxin from the site of injection
  • Paralysis of swallowing and respiration can be life-threatening
  • Symptoms of botulism

Related guidelines

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Sources: Goodman & Gilman 14e·Verified: 2026-05-10 · House clinical team