Nephrotoxicity (non-oliguric) - less common with once daily dosing; greater toxicity with longer duration and supratherapeutic trough levels; avoid concomitant nephrotoxins
Vestibulocochlear toxicity (irreversible)- suggest audiology testing if prolonged use
Can exacerbate neuromuscular blockade- e.g. contraindicated in patients with myasthenia gravis.