PHARMACOKINETICS OF FLOSEQUINAN IN ELDERLY PATIENTS WITH CHRONIC CONGESTIVE-HEART-FAILURE

We have investigated the pharmacokinetics of the direct vasodilator fl osequinan in elderly patients with congestive heart failure. Eight pat ients received a single dose of 50 mg, and 8 patients received once-da ily treatment with 25 mg for two weeks. In the single dose study, the t(max) of flosequinan was 2.5 h, C(max) was 1.17 mug.ml-1 and t1/2 was 5.63 h. The t(max) of the metabolite BTS 53554 was 20.3 h, C(max) was 1.44 mug.ml-1 and t1/2 was 62.0 h. BTS 53554 accumulated gradually in the 14-day repeated dose study and steady-state was reached after app roximately 2 weeks. Flosequinan was not found to accumulate. Adverse r eactions were not observed in either the single or repeated dose study . It is advisable to consider renal function and body weight when flos equinan is to be administered to elderly patients with congestive hear t failure. The initial dose should be 25 mg.