OBJECTIVES: To characterize patients suffering from restless legs syndrome (RLS) and assess their annual health care resources consumption in comparison with a population of average ambulatory patients seen by General Practitioners (GPs), in France. METHODS: This study was based on anonymous individual longitudinal medical records of adult patients suffering from RLS provided by physicians from a permanent panel of representative French GPs. RLS was defined accordingly to established diagnostic criteria. Patients with at least one complaint of legs and/or sleep symptoms suggestive of RLS in 2003 were included. Data about patients’ socio-demographic characteristics, clinical status, medical resources consumption and sick leaves over one year were collected retrospectively. For the cost comparison, RLS patients were matched for sex and age to a corresponding random population of patients followed by the same GPs. Average annual costs in € were estimated from the perspective of Health Insurance. RESULTS: A total of 515 RLS patients were included. Mean age was 63.8 years and 76% were female. 14% of patients had both complaints of leg and sleep symptoms, 59% only leg troubles and 27% only sleep disturbances. All together, RLS patients consumed significantly (p<0.0001) more health care resources than those from the comparison group. On average in 2003, they saw 11.6 times their GPs (versus 4.6 in the comparison group), 7 investigations were prescribed (versus 4.3) and they had had 46.8 drug prescriptions (versus 16.5). The mean annual medical cost of RLS patients’ follow-up by GPs was twice higher than that of average consulting patients (840€ versus 391€, p<0.0001). CONCLUSIONS: This study shows that patients satisfying to validated diagnostic criteria consumed significantly more medical resources than “ordinary” patients in primary care bearing in mind that RLS remains an unknown and under-diagnosed condition. This population deserves thus a special attention in order to optimize the treatment.