PHARMACOKINETIC BASIS OF NIFEDIPINE-DIGOXIN INTERACTION - A COMMENTARY

Elevation of plasma digoxin levels following concurrent administration of nifedipine have previously been reported. The mechanism for this i nteraction has not been fully explained, but may include a reduction i n volume of distribution of digoxin and/or reduction in the renal or n on-renal clearance of digoxin by nifedipine. The end result is probabl y an elevation of plasma concentrations of free (pharmacologically act ive) digoxin, which may lead to manifestation of side effects of digox in. This communication highlights the possible pharmacokinetic basis o f the reported digoxin-nifedipine interaction.