Absorption of oral ofloxacin after cytotoxic chemotherapy for haematological malignancy.

Abstract

Ten patients with newly diagnosed haematological malignancy were given ofloxacin, 400 mg daily orally, for antibacterial prophylaxis during neutropenia. Before cytotoxic chemotherapy was given, and on three occasions between days 2-3, 5-7 and 8-10 afterwards, blood samples were taken before and 1, 2, 3, 4, 6 and 10 h after administration of ofloxacin. Serum ofloxacin concentrations were measured by HPLC. Mean (range) pharmacokinetic parameters before chemotherapy were: Cmax, 6.1 (2.7-9.1) mg/L; AUC0-2, 7.5 (1.9-11.6) mg.h/L. On days 2-3 post-chemotherapy the values were reduced to: Cmax, 5.0 (3.6-7.3) mg/L; AUC0-2, 5.8 (1.9-7.8) mg.h/L. On days 5-7 the values were: Cmax, 6.1 (4.0-10.4) mg/L; AUC0-2, 8.5 (0.8-16.8) mg.h/L, and by days 8-10 the values were: Cmax, 6.4 (3.3-12.5) mg/L; AUC0-2, 8.6 (0.8-23.1) mg.h/L. There was a statistically significant difference between Cmax pre- and Cmax two to three days post-chemotherapy (paired t-test, P = 0.05). These changes are similar to those previously reported with ciprofloxacin but less marked.