Abstract
Permanent cochlear damage has been shown to occur in guinea pigs following the combined administration of kanamycin and furosemide. At the doses used, only a transient effect was measured with furosemide alone and no effect was detectable with kanamycin alone. This interaction results when a single subcutaneous dose of 400 mg/kg of kanamycin is followed in 2 hours by a single intravenous dose of furosemide. The dosage range for furosemide was 50 mg/kg for a just-detectable effect to 100 mg/kg for a very severe effect. Damage to the cochlea was ascertained by measures of the a.c. cochlear potential as well as surface preparation histology.