Combined effect of 3', 4'-dideoxykanamycin B and potent diuretics on the cochlea. (A scanning and transmission electron microscopic evaluation).

In investigations on the action of DKB (3' 4'-dideoxykanamycin B), and aminoglycoside type drug, on the inner ears of mice and guinea pigs by means of scanning and transmission electron microscopy, it was evident that the action of DKB against the inner ear is similar to that of kanamycin. When the same type of investigation was performed using the diuretics furosemide and ethacrynic acid, changes were observed in the stria vascularis. When DKB and ethacrynic acid, which show no long lasting defects when given independently, were administered concurrently in the same doses, a very high level of degeneration was found in the organs of Corti of guinea pigs. From the above results, it is evident that when two or more types of ototoxic drugs are administered concurrently, they have a potentiating action on the ear and care should be taken clinically concerning this point.