Objective: To assess the efficacy and safety of the dopamine agonist cabergol ine (CAB) in patients with restless legs syndrome (RLS). Methods: Patients with moderate to severe RLS were randomized into four groups receiving placebo, 0.5 m g, 1 mg, or 2 mg CAB once daily in a double-blind, placebo-controlled, multi center dose-finding trial followed by an open long-term extension trial of 4 7 weeks. Efficacy was assessed with the RLS-6 scales and International RLS Stu dy Group severity scale (IRLS). Results: A total of 85 patients (age 56 ± 10 ye ars, 71% females) were treated. Severity of RLS-6 scale symptoms during the night (the primary endpoint) was markedly improved by all CAB doses compared to placebo (placebo: - 1.4 ± 3.1, 0.5mg CAB: - 4.2 ± 3.0 [p =0.0082], 1.0 mg CA B: - 4.0 ± 2.9 [p = 0.0040], 2.0 mg CAB: - 4.8 ± 3.7 [p = 0.0026]). Similar results were found for the RLS severity at bedtime and during the day, IRLS, and satisfaction with sleep. A stable, clinically relevant improvement was achieved in all efficacy measures (severity during the night: change between last assess ment and baseline: - 5.6 ± 2.5, rate of remission: 71.2% ) throughout 1 year with a mean CAB dose of 2.2 mg per day. During longterm treatment, 6 of 66 treat ed patients were affected (n = 2) or possibly affected (n = 4) by mild augmentat ion. Under CAB therapy up to 1 year, 11 of 85 patients discontinued treatment du e to a drug-related adverse event. Conclusions: Cabergoline is an efficacious and well-tolerated option for the treatment of restless legs symptoms during t he night and the day. Objective: To assess the efficacy and safety of the dopamine agonist cabergoline ine (CAB) in patients with restless legs syndrome (RLS). Methods: Patients with moderate to severe RLS were randomized into four groups receiving placebo, 0.5 mg, 1 mg, or 2 mg CAB once daily in a double-blind, placebo-controlled, multi center dose-finding trial followed by an open long-term extension trial of 4 weeks. Efficacy was assessed with the RLS-6 scales and International RLS Stu dy Group Severity of RLS-6 scale symptoms during the night (the primary endpoint) was markedly improved by all CAB doses (age 56 ± 10 ye ars, 71% females) were treated. compared to placebo (placebo: -1.4 ± 3.1, 0.5 mg CAB: -4.2 ± 3.0 [p = 0.0082], 1.0 mg CA B: -4.0 ± 2.9 [p = 0.0040], 2.0 mg CAB: -4.8 ± 3.7 [p = 0.0026]). Similar results were found for the RLS severity at bedtime and during the day, IRLS, and satisfaction with sleep. A stable, clinically relevan t improvement was achieved in all efficacy measures (severity during the night: change between last assessment and baseline: - 5.6 ± 2.5, rate of remission: 71.2%) over 1 year with a mean CAB dose of 2.2 mg per day. treatment, 6 of 66 treat ed patients were affected (n = 2) or possibly affected (n = 4) by mild augmentat ion. Under CAB therapy up to 1 year, 11 of 85 patients discontinued treatment du e to a drug-related adverse event. Conclusions: Cabergoline is an efficacious and well-tolerated option for the treatment of restless legs symptoms during t he night and the day.