Pivampicillin, an ester of ampicillin hydrolyzed after oral administration, was given to 25 elderly patients suffering from urinary tract infections. Daily dosage was 3 x 700 mg. This treatment was well tolerated and gave good clinical results. Antibiotic concentration in serum, obtained 2 and 6 hr after oral administration of 700 mg of pivampicillin (an amount equivalent to 500 mg of ampicillin) averaged respectively 6.1 and 1.5 μg/ml; these levels are two times higher than those produced by ampicillin administered orally at the same dose.SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe