Accumulation of New Quinolones in the Blood of Elderly Patients

We studied the correlations between renal func­ tion and age, serum concentrations of quinolones and age, and serum concentrations of quinolones and renal function in 189 patients aged 51 to 87 (mean 70.5 ± 7.7) years who were undergoing transurethral resection of the prostate with benign prostatic hyperplasia and who did not have hepatic and/or renal diseases. Renal function was evalu­ ated by measuring 24-hour creatinine clearance (CLCR), serum creatinine, and blood urea nitrogen (BUN) before administration of the study drugs. Norfloxacin, ofloxacin, enoxacin, ciprofloxacin and lomefloxacin were administered orally at a dosage of 200mg tid for 3 days. Drug serum concentra­ tions 5.5 hours and approximately 17 hours after final administration were measured by the agar well method. There was significant correlation between age and renal function (CLCR, p enoxacin > ciprofloxacin = norfloxacin. This order corre­ sponds with that for the urinary excretion rate. In conclusion, serum concentrations of the quinolones rise with aging, because renal function declines. They seem more likely to rise with oflox­ acin, lomefloxacin and enoxacin, which had higher urinary excretion rates; therefore, careful adjust­ ment of dosage and monitoring of serum concen­ trations are required to prevent adverse reactions when these drugs are administered to elderly patients.