Efficacy and side effects of botulinum toxin treatment for blepharospasm and hemifacial spasm.

Abstract

To analyse the effectiveness and rate of side effects of botulinum toxin treatment for blepharospasm and hemifacial spasm. In a prospective trial, 81 patients with blepharospasm and 70 with hemifacial spasm were treated with botulinum toxin A in the neuroophthalmology clinic at St Vincent's Hospital, Melbourne. Some 989 treatments were given and the mean follow-up time was 28.7 months. The duration of action was longer for patients with hemifacial spasm than for those with blepharospasm (median 12.0 weeks compared with 7.0 weeks, P < 0.0001). There was no change in the duration of effect over time with repeated treatments of the same dose (F = 0.4, P > 0.05). Once an effective dosage was reached, increasing the dose further did not prolong the duration of effect. There were no systemic side effects, but there were a number of local transient side effects. The most significant side effect was ptosis, which occurred in 12% of treatments given to those patients with blepharospasm and hemifacial spasm. Botulinum toxin is an effective treatment for blepharospasm and hemifacial spasm, but there are a number of side effects, the most significant being ptosis.