NEW DOSING REGIMENS FOR AMINOGLYCOSIDE ANTIBIOTICS

Aminoglycosides are commonly used to treat severe infections due to aerobic Gram-negative bacillary because of their broad-spectrum and reliable antimicrobial activity against these microorganisms. However, clinical efficacy has been disappointing, and renal, auditory and vestibular toxicity have placed severe restrictions on their general utility. Recently a new dosing regimen, namely, giving the total daily dose of aminoglycoside once daily, rather in divided doses, has recently been proposed both to improve efficacy and possibly reduce toxicity, as suggested by pharmacodynamic data from experimental models of infection in small animals. Nevertheless the existing clinical data, although favorable for single daily dosing of aminoglycosides, are limited mostly to mild infections in non-compromised patients. Definitive recommendations await further controlled clinical evaluation in appropriate patient populations. Until then, there are only a few clinical situations where once daily dosing of aminoglycosides can be used with confidence: 1) when an aminoglycoside is used in combination with a beta-lactam, where tissue concentrations of the beta-lactam are maintained above the MIC throughout the dosing interval; or 2) in the rare circumstance when an aminoglycoside is used alone to treat uncomplicated urinary tract infection due to pathogens resistant to multiple other antimicrobial agents.