[Evaluation of microsomal enzyme function in the liver in patients with duodenal ulcer treated with famotidine].

The studies of microsomal liver enzyme activity by means of a respiratory test with 14C-aminopyrine (ABT) were carried out in 20 patients with duodenal ulcer treated for eight weeks with famotidine. The respiratory test was performed before the introduction of treatment (group I), after four weeks of treatment (group II), and after eight weeks of treatment (group III). The mean value of the respiratory test before treatment was 5.32% of the dose/h. After four weeks of treatment with famotidine a significant decrease was found of the test value (x = 4.79% of the dose/h). An even stronger inhibitory action of famotidine on the microsomal system was shown after eight weeks of the treatment (x = 4.46% of the dose/h). These results evidence a depressive effect of famotidine on the activity of liver monooxygenases. In patients taking this drug, other drugs metabolised in the hepatocyte microsomal system should be used with high caution, as well as those which are known to be inhibitors of this system.