High frequency deafness usually occurs first and can be detected only by audiometric testing.
The risk of aminoglycoside-induced ototoxicity is greater in patients with renal damage. Neurotoxicity, manifested as vestibular and permanent bilateral auditory ototoxicity, can occur in patients with preexisting renal damage and in patients with normal renal function treated at higher doses and/or for periods longer than those recommended.
Safety for treatment periods which are longer than 14 days has not been established. Patients treated with parenteral aminoglycosides should be under close clinical observation because of the potential ototoxicity and nephrotoxicity associated with their use.
