The benefits of using oral fluid as a biological matrix include the ability to detect recent drug use, ease of collection, and the collection process can be observed to prevent adulteration of the sample. ... Thomson eXtreme Filter Vials provide a simple and efficient extraction technique that has demonstrated adequate analyte recovery, reduced matrix interferences and the elimination of solvent waste and other consumables. This project specifically explores the efficacy of these vials in extracting a wide range of antidepressants in oral fluid specimens.