Lack of relationship between debrisoquine oxidation phenotype and the pharmacokinetics and first dose effect of prazosin.

The relationship between debrisoquine oxidation phenotype and the pharmacokinetics and pharmacodynamics of a single oral dose of prazosin has been studied in eight hypertensive patients (four extensive and four poor metabolisers). No significant differences between the two phenotypes were observed in either the area under the plasma prazosin concentration-time curve, the terminal half-life or the first-dose effect of prazosin.