Drugs in Oral Fluid

Abstract

The analysis of oral fluid samples for drugs of abuse has been reported for over 30 years. With improvements in method and instrument sensitivity and the development of point of collection screening devices, the popularity of using oral fluid as a sample type for toxicological investigations has increased more recently. There are many considerations that need to be made prior to using oral fluid analysis within investigations and studies. These include an understanding of the physiology of oral fluid and the mechanisms by which drugs enter into oral fluid and the impacts of routes of administration, particularly in relation to the deposition of drugs taken orally, smoked or snorted in the oral or nasal cavities. The methods used for the collection of oral fluid samples can also impact on the detection of different drugs of abuse, through the stimulation of the production of saliva, retention of drugs of abuse on collection devices, instability of certain analytes and variation in the volume of oral fluid collected. This chapter investigates these issues as well as looking at other important factors when considering the use of oral fluid, such as the detection windows and the detection of inadvertent exposure to drugs.