[Metabolism and kinetics of ampicillin elimination in cirrhosis. Therapeutical consequences. (author's transl)].

In cirrhotic patients, the authors studied the modification of the pharmacokinetics of ampicillin in the plasma and in the ascitic fluid, as well as its concentration in the urine. The influence of the jaundice, the ascites and diuretics were studied. In cirrhosis, dilution and elimination of the antibiotic are modified, as is shown by the increase in T 1/2 alpha and T 1/2 beta. These anomalies seem to be due essentially to modifications in the distribution volume; the degree of hepatocellular insufficiency does not appear to be of importance. The ascites acts as an independent compartment, into which the antibiotic's passage in slight. The practical consequences are the following: less frequent injections, increasing of the fractionated doses, in situ injections of ampicillin in cases of infection of the ascitic liquid.