Abstract
The pharmacokinetics of medroxalol are described in normal subjects and compared with those of labetalol. Both drugs were administered in doses of 400 mg orally and 1 mg/kg intravenously. The data for both drugs was most appropriately described by a two compartment model. For oral medroxalol the clinical pharmacokinetic parameters were a terminal elimination half-life (t 1/2,Z) of 15.6 h, a peak level of 450 ng/ml and a time to peak of 2-3 h. Following intravenous medroxalol the bioavailability was calculated as 64%, the plasma clearance was 948 ml/min and the t 1/2,Z was 7.3 h. The t 1/2,Z following intravenous administration was significantly shorter than that following oral administration. The significant differences between medroxalol and labetalol were in time to peak, respectively 2.3 and 1.1 h; oral t 1/2,Z, 15.6 and 5.5 h; clearance 948 and 1560 ml/min; and bioavailability, 64 and 20%. Despite the pharmacokinetic differences a similar plasma concentration-hypotensive effect relationship was described for each drug.
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Selected References
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