Rapid onset of action of levodopa in restless legs syndrome : A double-blind, randomized, multicenter, crossover trial

To investigate the efficacy and safety of levodopa plus benserazide in the treatment of restless legs syndrome (RLS), in terms of the frequency of periodic limb movements (PLMs), objective and subjective criteria of sleep, onset of action, and withdrawal effects. A randomized, double-blind, placebo-controlled, multicenter, crossover trial, with two 4-week treatment periods. Outpatient units of three specialist centers in Germany. Eligible patients had to fulfill the diagnostic criteria of the International RLS Study Group and have sleep disturbances and PLMs during sleep shown on polysomnography at screening. Thirty-five patients were recruited, of whom 32 (13 men, 19 women) completed the study. Patients received a single dose of standard-release levodopa/benserazide 100/25 mg or placebo at bedtime each night for 4 weeks, before crossing over to receive the alternative treatment for a further 4 weeks; the dose could be doubled if required. The average dosages were 159 +/- 31 mg of levodopa and 1.56 +/- 0.29 capsules of placebo. Levodopa/benserazide significantly reduced the number of PLMs per hour (p