Conversion of Benzylpenicillin to Penicilloic Acid in Patients with Chronic Bronchial Infections

A colorimetric method was modified to estimate the levels of benzylpenicillin and its penicilloic acid in urine. When benzylpenicillin was given orally to healthy volunteers, both it and its penicilloic acid were detected in the urine. When benzylpenicillin was given by intramuscular injections to these volunteers, only benzylpenicillin was detected in the urine. Patients suffering from chronic bronchial infections that exhibited beta-lactamase producing gram-negative bacteria in their sputum were given benzylpenicillin intramuscularly. It was found that both benzylpenicillin and penicilloic acid were recovered from the urine of such patients.