Sensitive gas chromatographic determination of trifluoperazine in human plasma

Plasma trifluoperazine levels of patients taking a single 20-mg dose of trifluoperazine were measured by a sensitive and linear method. The low detection limit of 0.1 ng/ml plasma was obtained through use of a highly sensitive nitrogen—phosphorus detector combined with an efficient extraction method. Recovery of trifluoperazine added to human plasma was 96%. Data are presented on the stability of trifluoperazine in refrigerated human plasma.