Selected ion monitoring assay for meclizine in human plasma.

A method has been developed for the quantification of meclizine in human plasma using gas chromatography mass spectrometry. Pentadeuterated meclizine was synthesized and used as an internal standard. The method gave linear results over a concentration range of 5-200 ng ml-1 and was used to determine plasma levels of meclizine following administration to a male volunteer.