Co-dispensing of contraindicated medications in patients using cisapride in Italy

Purpose: To investigate the co-dispensing of contraindicated medications in patients using cisapride in an Italian population. Methods: The study included patients who had at least one cisapride prescription dispensed between 1 April 1997 and 30 September 2000. The proportion of cisapride users with concomitant medications, the proportion of prescriptions of cisapride with an overlapping dispensing of a contraindicated medication and the proportion of person-days of cisapride use concomitant with contraindicated medications, were calculated. Results: In the 4-year study period, 249 740 total cisapride prescriptions, which corresponded to 382 835 packages, were dispensed to 91 204 users (52 442 female, 57.5%). Concomitant use of contraindicated drugs was identified in 4403 cisapride users (4.83%). Throughout the study period, there was an increase in the proportion of cisapride users with contraindicated co-prescriptions: 4.29% in 1997, 4.99% in 1998, 5.15% in 1999, but a decline to 3.34% in 2000. In each year, this figure was higher in males, with the highest proportion reported in 1999 (5.50%). A total of 7215 cisapride prescriptions (2.85%) were concomitant with contraindicated drugs, ranging from 2.27% in September 1998 to 3.55% in January 1999. Cisapride prescriptions were most frequently associated with macrolide antibiotics (1.14%) and class III antiarrhythmics (1.03%). Conclusions: In the period 1997-2000, a substantial proportion of cisapride prescriptions were concomitant with contraindicated medications. In Italy in 1998, the National Health Authority issued a bulletin warning about the risk of serious arrhythmias after concomitant use of contraindicated drugs. Despite this warning, there was no reduction in contraindicated drug uses.