botulinum toxin

a powerful nerve toxin, produced by the bacterium Clostridium botulinum, that has proved effective, in minute dosage, for the treatment of various conditions of muscle overaction, such as strabismus (squint) and various dystonic conditions (see DYSTONIA ), including spasm of the orbicularis muscle in patients with BLEPHAROSPASM ; it is administered by injection. It is also used to treat ACHALASIA , being injected through an endoscope into the gastro-oesophageal sphincter, and for relieving the spastic paralysis associated with cerebral palsy. Side-effects include prolonged local muscle paralysis.