ABSTRACT
Modern laboratory testing of blood and urine, and occasionally other body fluids, breath, or body tissue has become so accurate and so sensitive that the use of addicting drugs of most major groups, even after 10 half lives, may be detected. In standard laboratory screening the emphasis is on certainty of significant levels rather than traces of drug. In this chapter we will discuss the use of the laboratory to confirm drug usage, and to establish which drugs have been used. A monograph is available. 1
