Role of dopamine receptor agonists in the treatment of restless legs syndrome.

The restless legs syndrome (RLS) is defined by four essential criteria obligatory for clinical diagnosis which were established, and recently revised, by the International RLS Study Group. These are (i) the urge to move the legs, usually accompanied or caused by uncomfortable and unpleasant sensations in the legs, which are (ii) worse during rest/inactivity, (iii) partially or totally relieved by movement and (iv) worse at night/in the evening. Treatment with levodopa leads to symptom relief, but augmentation (occurrence of symptoms before levodopa administration in the evening) may occur, limiting the long-term use of this drug. This article gives an overview of the treatment in general and the role of dopamine receptor agonists in the therapy of RLS and periodic limb movements (PLMs). Dopamine receptor agonists are widely used as an effective treatment for RLS and PLMs, presumably because of their longer half-lives, lower likelihood of augmentation and good tolerability compared with levodopa. It was shown that, for example, pergolide, ropinirole, pramipexole and cabergoline alleviated RLS symptoms in 70-90% of patients. A new non-oral (transdermal) formulation of one dopamine receptor agonist, rotigotine, has recently been developed and shown to be efficacious in RLS. Further research should focus on long-term observations and comparisons of different dopamine receptor agonists in RLS.