Neurotoxicity of antibacterial therapy.

The increasing variety of drugs available for the treatment of bacterial infections has simultaneously increased the potential for toxicity. Neurologic toxicity of antibacterial therapy is generally underestimated in scope and severity; it may be classified as central, peripheral, or due to drug-interactions, several of which are potentially life-threatening. beta-Lactams and the quinolones are the drugs most commonly associated with seizures and encephalopathy. Drug-induced ototoxicity is common, and sensitive tests are now available for early diagnosis of both cochlear and vestibular toxicity. Testing in clinical practice is best restricted to subgroups at high risk. The aminoglycosides, tetracyclines, clindamycin, erythromycin, polymyxins, and possibly ampicillin have the potential to aggravate neuromuscular disease. Ethambutol, isoniazid, and chloramphenicol are toxic to the optic nerve; bismuth can cause a myoclonic encephalopathy. A number of less common and/or unusual toxicities are also discussed.