Analysis of prazosin in plasma by a sensitive high-performance liquid chromatographic-fluorescence method.

A specific high-performance liquid chromatographic-fluorescence method for the quantitative analysis of prazosin in plasma at concentrations down to 0.2 ng/ml is described. The method involves the coextraction of drug and an internal standard from alkalinized plasma followed by a simple purification step prior to evaporation and high-performance liquid chromatographic-fluorescence analysis. The method is sufficiently sensitive to allow pharmacokinetic analyses of 1-mg doses through five half-lives, with a relative standard deviation of 12%.