[Present status of nitroxoline]

Abstract

Nitroxoline (8-hydroxy-5-nitroquinoline) has been used since 1962 in the treatment of urinary tract infections especially those due to gram negative bacilli (E. coli). The current renewal of the drug is in relation to the recently shown activity of nitroxoline against fungi (Candida, Torulopsis), Mycoplasma and U. urealyticum, as well as Trichomonas. In order to update the knowledge of the drug, the aim of this study was a pharmacokinetic study in serum and urines collected after administration of one single dose (2 X 100 mg) and after multiple doses (200 mg X 3). Eight healthy volunteers were included in the study. The assays were carried out by means of the microbiological procedure and HPLC comparatively in the same samples. From the results several comments should be made: 1) In all subjects, serum levels were measurable 15 to 30 min. after administration, suggesting a rapid absorption. 2) Despite individual variations due to oral administration, pharmacokinetic parameters could be calculated: Tmax: 1.75 +/- 1.04 h; Cmax: 5.59 +/- 3.15 mg/l; t 1/2 beta: 2.63 +/- 2.66 h. 3) The hepatic metabolization of the drug into conjugated derivatives occurs early as shown by early levels of conjugated nitroxoline as measured by means of HPLC; the metabolization seems to be variable according to the subjects quantitatively and as for its kinetics. 4) The urinary elimination of nitroxoline is extremely rapid, and high levels of free drug and conjugated derivatives were measured at the 1st hour after the administration. Persistent high levels were measured at the 10th and 24th hours.(ABSTRACT TRUNCATED AT 250 WORDS)