Drugs associated with restless legs syndrome: a case/noncase study in the French Pharmacovigilance Database

Several case reports have suggested that drugs could induce restless legs syndrome. However, no systematic review of this adverse drug reaction (ADR) in a pharmacovigilance database has been published.

To assess the frequency of restless legs syndrome in the French Pharmacovigilance Database.

We selected all ADR reports from January 1, 1984 to December 31, 2009 coded as restless legs syndrome. Restless legs syndrome diagnosis was validated from case descriptions. Using a case/noncase approach, reporting odds ratio and 95% confidence interval were calculated for "suspected'' drugs with 2 or more observations.

Twenty-six ADR reports were found. Four cases were excluded because of alternative diagnosis. Fourteen cases were women (64%). Median age was 57. Most frequently suspected drugs were antidepressants (reporting odds ratio, 15.9 [6.4-39.7]; amitriptyline, escitalopram, mianserine, mirtazapine, duloxetine), neuroleptics (17.8 [6.1-51.7]; thioridazine, loxapine, risperidone, aripiprazole) or tramadol (18.2 [6.3-52.8]).

Restless legs syndrome is a very rare ADR that was more frequently reported in association with antidepressants, neuroleptics, or tramadol.