Interactions Between Cardiac Glycosides and Other Substances in the Body

It is well documented that cardiac glycosides require careful dosage adjustment in the individual patient to achieve satisfactory clinical responses without toxic symptoms. Many factors contribute to the variation in dosage between patients, for instance, variable absorption, differences in disposition pharmacokinetics, and severity of the heart disease. In addition, interactions with other substances have been found to explain observations of resistance or increased sensitivity to treatment with cardiac glycosides.