Antipyrine estimations in the rabbit using gas--liquid chromatography: a reliable method for studying factors affecting oxidative drug metabolism.

The application of a gas--liquid chromatographic (GLC) method to measurements of antipyrine in plasma for the estimation of antipyrine half-life (T1/2) in the rabbit is described and is compared with previous GLC methods. It has been established that the estimation of antipyrine can be achieved with acceptable precision and that rabbits can act as their own controls in the study of factors that might alter T1/2. Iproniazid phosphate, 50 mg/kg IP, was shown to produce a mean increase of 170% in T1/2.