infectious diseases
Aminoglycosides
Adverse Effects of Aminoglycosides
All aminoglycosides cause Renal toxicity (often reversible) Vestibular and auditory toxicity (often irreversible) Prolongation of effects of neuromuscular blockers Symptoms and signs of vestibular damage are vertigo and ataxia. Risk factorsfor renal, vestibular, and auditory toxicity are Frequent or very high doses Very high blood levels of the drug Long duration of therapy (particularly>3 days) Older age A preexisting renal disorder Coadministration ofvancomycin,cyclosporine,amphotericin B, iodinated contrast agents, or other nephrotoxins For auditory toxicity, a genetic predisposition, preexisting hearing problems, and coadministration of loop diuretics High doses given over a long period of time typically cause more concern about renal toxicity, but even low doses given for a short time can worsen renal function. Patients receiving aminoglycosides for>2 weeks and those at risk of vestibular and auditory toxicity should be monitored with serial audiography. At the first sign of toxicity, the drug should be stopped (if possible), or dosing should be adjusted. Aminoglycosides can prolong the effect of neuromuscular blockers (eg,succinylcholine, curare-like drugs) and worsen weakness in disorders affecting neuromuscular transmission (eg, myasthenia gravis). These effects are particularly likely when the drug is given too rapidly or serum levels are excessively high. The effects sometimes resolve more rapidly if patients are givenneostigmineor IV calcium. Other neurologic effects include paresthesias and peripheral neuropathy. Hypersensitivity reactions are uncommon except for contact dermatitis due to topicalneomycin. High oral doses ofneomycincan cause malabsorption. 