Gentamicin and penicillin in the treatment of severe respiratory infections.

A combination of penicillin and gentamicin has been used for severely ill patients in a respiratory intensive care ward. It has been shown that predictable mean blood levels of gentamicin can be obtained in these patients by relating the dose to surface area (60 mg/m2/8 h). When renal function was initially normal it did not deteriorate during the course of therapy (10 days); gentamicin assays are not essential for safe treatment. In patients with renal failure, increasing the interval between doses also resulted in satisfactory levels, but close monitoring of the serum creatinine level is considered necessary. No clinical difference could be detected when gentamicin was given by constant or intermittent infusion.