Key Results:
Donepezil significantly prolonged the PR (P=0.04), QRS (P=0.04) and QT (P=0.002) intervals. The increase in QT intervals remained significant on correction for heart rate; resulting in 8 (13.6%) patients developing high arrhythmogenic risk based on assessment using QT nomogram plots. Concomitant use of tricyclic antidepressants was associated with significant QT prolongation, while use of rate limiting calcium channel blockers was associated with significant PR prolongation, and beta-blockers with reduction in heart rate.