Interchangeability of Digoxin Tablets

Abstract

The bioavailability of 2 kinds of digoxin tablets (0.25mg) on the Japanese market was compared. Two tablets were given daily in empty stomach to 3 each of healthy men and women. Serum levels of digoxin were measured by radioimmunoassay before and 0.5, 1, 2, 4 and 6 hours after the administration.In vitro tests were performed to determine the weight variation, hardness, content, disintegration time and dissolution time of the tablets. As a result, some differences in the test items were found although they might be caused by additives in the tablets.There was no statistically significant difference in the serum level among the products because of the fact that the difference among the human subjects was larger than that among the products. Therefore, it can be said on the basis of the in vitro and in vivo tests that the two products are interchangeable.But the blood level of digoxin should occasionally be determined in patients under this therapy because of individual difference in bioavilability.