A report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology concludes that local injection of type A botulinum toxin (Botox) is proven as a safe and efficacious modality for the treatment of blepharospasm, cervical dystonia, and hemifacial spasm. The literature is reviewed in detail and 62 references are provided. Botox causes muscle paralysis by acting at peripheral nerve endings to block the release of acetylcholine. The effectiveness of the injections is transient lasting on the average four months. Side effects are transient, well tolerated, and amenable to treatment when indicated. 
COMMENT. Efficacy of this treatment in children parallels that in adults but safety has not been studied. Use during pregnancy or lactation is not recommended. FDA approval for the use of Botox has been obtained for the treatment of strabismus and blepharospasm associated with dystonia in patients 12 years of age and older.
Snow BJ et al report a beneficial effect of botulinum toxin on focal spasticity of leg adductors in nine patients with multiple sclerosis.