Studies of Plasma Quinidine Content

Abstract

Quinidine sulfate, orally administered in tablets coated with a material delaying their absorption, produces concentration curves in the blood serum similar to those of uncoated tablets. However, there is a delay in the appearance and the attaining of maximum concentrations with the coated tablets, although higher levels may persist for 12 hours. Defects in coating may cause faulty failure of absorption. The advantages of using such a preparation of quinidine are: (1) avoidance of nausea in susceptible persons, (2) providing effective concentrations of the drug during the night and thereby preventing nocturnal attacks of arrhythmias, and (3) providing greater concentrations of the drug in the morning, when attempts at conversions of arrhythmias may require therapy over several days or more.