The influence of cisapride and clarithromycin on QT intervals in healthy volunteers

12 healthy volunteers

Cisapride (10 mg 4 times a day) for 10 days with concomitant clarithromycin (500 mg twice a day) from days 6 through 10, or clarithromycin (500 mg twice a day) for 10 days combined with cisapride (10 mg 4 times a day) from days 6 through 10

Baseline (pretreatment) and monotherapy with either cisapride or clarithromycin alone

Pharmacokinetic changes (plasma drug levels) and increased QT intervals (QTc elevations)surrogate