Studies on the Absorption of Pivampicillin and Ampicillin

Abstract

In a cross-over study in 24 patients the concentrations of ampicillin in serum after single oral doses of pivampicillin 700 mg, corresponding to 500 mg of ampicillin, and ampicillin trihydrate 670 mg and 500 mg were studied. The concentrations of ampicillin in serum were determined by an agar-plate diffusion method using Sarcina lutea ATCC 9341 as test organism. Serum concentrations of ampicillin were significantly higher after pivampicillin than after the other preparations. The renal function was evaluated with repeated inulin tests and serum creatinine determinations. 18 patients were studied both during acute illness and during convalescence. Their renal function was found to be the same in both stages as well as the serum concentrations of ampicillin. Patients with reduced renal function were found to peak higher and later than those with normal renal function.