A multi-centre, double-blind trial of tizanidine, a new antispastic agent, in spasticity associated with hemiplegia.

A double-blind study was carried out in 105 patients with chronic spasticity associated with hemiplegia in order to compare the efficacy and tolerability of tizanidine with that of diazepam. Dosage was increased progressively, if tolerated, to a maximum of 24 mg tizanidine or 30 mg diazepam per day at the end of 2 weeks. The optimum dosage was then maintained for 6 weeks. Efficacy and tolerability parameters were assessed after 2 and 8-weeks' therapy. Patients on tizanidine but not those on diazepam showed a statistically significant improvement in functional status, as assessed by walking distance on flat ground. Analysis of the stretch reflex in four groups of muscles showed that both tizanidine and diazepam reduced the duration of contractions and increased the angle at which contraction occurred, but there were no significant differences between the two drugs. Clonus of the triceps surae resolved in 48% of tizanidine and 40% of diazepam patients. Evaluation of the effect of therapy revealed an improvement with each drug in approximately 83% of patients, with the overall evaluation being slightly (but non-significantly) in favour of tizanidine. There were fewer discontinuations of treatment in the tizanidine group as a result of side-effects. It would appear, therefore, that tizanidine is an effective and well-tolerated drug in the treatment of cerebral spasticity.