High-performance liquid chromatographic assay for azatadine in human urine

A high-performance liquid chromatographic assay for the quantitative determination of azatadine and a base (1 M sodium hydroxide) hydrolyzable conjugate of azatadine in human urine has been developed. Reversed-phase separation of azatadine and the internal standard, 8-chloroazatadine, was accomplished on a 300 X 3.9 mm I.D. mu Bondapak CN column. Following liquid-liquid extraction from urine, azatadine was quantitatively determined by UV detection at 214 nm. No interferences were observed in the extracts obtained from drug-free urine. Detector response (peak area ratio) was linear from 10 to 2500 ng/ml. This method has been shown to provide accurate and precise determinations of the unchanged and hydrolyzed drug in human urine, following the twice daily oral administration (1-2 mg) of azatadine maleate.