Polyradiculoneuritis after botulinum toxin therapy for cervical dystonia.

A 40-year-old man with cervical dystonia developed an acute inflammatory demyelinating polyradiculoneuritis after botulinum toxin type A treatment. Some cases of idiopathic brachial plexopathy and polyradiculoneuritis have been reported to date. Although a causal relationship is not firmly established, the clinical temporal profile suggests a pathogenic relationship. In patients with cervical dystonia, further use of type A botulinum toxin should be considered contraindicated, and the use of another type of botulinum toxin should be taken into consideration.