Incidence of potential drug interactions in co-prescription of statins and macrolide antibiotics in Croatia during the 14 year period.

The objective of this study was to determine the number of patients on the national level that took macrolide antibiotics along with chronic statin therapy in Croatia in the period from 2002 to 2015, and to analyse prescription patterns. In 2002, statins were used in the treatment of 2.6% of the total number of insured persons in Croatia. By 2015, this number increased to 8.4%. In the period studied, on average 15.3% of the patients on statin therapy were co-prescribed macrolide antibiotics. Erythromycin was combined with different statins on average in 1.4% of cases, clarithromycin in 25.5% and azithromycin in 73.2% of the cases. Relative frequency of combining statins with macrolides was similar for all statins. On average, 11.5% of patients on concomitant statin-macrolide therapy were taking high-dose statins. On average, 90% of these co-prescriptions can lead to potentially clinically significant DDIs (X, D, C). The co-prescription of statins and macrolide antibiotics in the Republic of Croatia is increasing. The greatest number of co-prescriptions with macrolides were with atorvastatin and simvastatin.