Botulinum toxin injections for cervical dystonia.

We followed 205 of 232 patients with medically intractable cervical dystonia for at least 3 months and up to 4 years, during which time they received 1,074 injections in 505 visits. One hundred forty-five of the 205 patients (71%) improved substantially (global rating greater than or equal to 2; from 0 = no response to 4 = marked improvement in severity and function) after 1 or more visits. Of the 89 patients who reported pain, 68 (76%) had almost complete relief of their pain. While most patients noted improvement within the 1st week after injection, some had a latency of up to 8.5 weeks. Duration of maximum benefit lasted up to 12.5 months in some, but the average was 11.2 weeks. Only 58 of 205 (28%) patients, seen in 76 of 505 visits (15% of all visits), had complications, primarily mild dysphagia (35 patients) or neck weakness (17 patients). We conclude that botulinum toxin is a safe and effective therapy for most patients with cervical dystonia.