Experimental study of the ototoxicity of fosfomycin

Two tenths ml of 5% fosfomycin sodium solution (10 mg) was injected into the tympanic cavity of guinea pigs once a day for 7 days. Auditory brain stem response (ABR) was performed to examine the effect of the drug on the experimental animals. Additionally, a scanning electron microscopic study was also performed to observe the effect of the drug on outer hair cells of the organ of Corti and on vestibular sensory epithelia. No degenerative changes were observed in outer hair cell cilia of the organ of Corti and the vestibular sensory cilia at 1 day, 7 days, 14 days and 1 month after injection. No changes of the threshold of ABR were also noticed.