A double-blind comparative trial of new muscle relaxant, tizanidine (DS 103-282), and baclofen in the treatment of chronic spasticity in multiple sclerosis.

A double-blind trial with two parallel groups was carried out to compare the antispastic effect and tolerability of a new muscle relaxant, tizanidine (DS 103-282), with those of baclofen in the treatment of spasticity due to multiple sclerosis. Twenty-one hospitalized patients with stable spasticity participated in the 6-week trial. Eleven received tizanidine and 10 baclofen in gradually increasing daily doses. The optimal daily dose of tizanidine was between 8 and 36 mg and that of baclofen between 10 and 80 mg. Overall spastic state, spasms and clonus were similarly improved with both medications. In contrast, muscle strength, bladder function and the activities of daily living were more improved on tizanidine than on baclofen. Tiredness was the most frequent side-effect on tizanidine and muscle weakness on baclofen. The laboratory tests did not show any pathological changes with either medication. According to these results, tizanidine provides a new therapeutic alternative in the treatment of spasticity.