Dopaminergic Agents in Restless Legs Syndrome and Periodic Limb Movements of Sleep: Response and Complications of Extended Treatment in 49 Cases

Restless legs syndrome (RLS) is a common neurosensorimotor disorder that presents with paresthesias, sleep disturbances and, in most cases, periodic limb movements of sleep (PLMS). Although many treatments have been described, interest has recently been focused on dopaminergic mechanisms of etiology and treatment. The dopamine agonists L-dopa/carbidopa, bromocriptine mesylate or both were initiated in 49 patients with RLS/PLMS who sought consultation at a sleep disorders center. This retrospective study describes the symptoms, time course of response and complications in 36 men and 13 women with a mean age of 53.9 years. Only 47 of the patients were available for extended follow-up. The most common presenting complaints were the sensation of restless legs and sleep maintenance insomnia lasting over 20 years. In the extended follow-up group of 47, four failed to respond to L-dopa or bromocriptine, five discontinued treatment because of side effects and two reported loss of therapeutic effect within the first month. Between month one and six, only three additional subjects discontinued treatment. At a mean follow-up of 283 days (SD 316), 33 patients continued on L-dopa/carbidopa at a mean bedtime dose of 160 mg L-dopa (SD 300). Treatment-emergent morning leg restlessness developed in eight patients, seven of whom required daytime medication for relief. Other side effects, generally nausea, occurred in only eight of 43 patients. Psychiatric side effects of dyskinesia were not seen. The > 70% long-term response is comparable to other studies in the literature.