Stigning i plasmakoncentrationen af loratadin er rapporteret efter samtidig anvendelse af ketoconazol, erythromycin og cimetidin i kontrollerede studier, dog uden klinisk signifikante ændringer (inklusive elektrokardiogram).
Increase in plasma concentrations of loratadine has been reported after concomitant use with ketoconazole, erythromycin, and cimetidine in controlled trials, but without clinically significant changes (including electrocardiographic).