Excerpted Chapters from Drug Injury: Liability, Analysis and Prevention – Chapter 43 – Forensic Drug Testing — Chapter 44 – Drug Testing in the Workplace (PDF – Full chapters) 43.1 Introduction Review of this chapter will assist counsel in understanding the tests, in communicating with their own experts, and also in cross-examining opposing experts. In order for a scientist, toxicologist, pharmacologist, pharmacist, or pathologist to correlate drug action or effects with the drug found in the body, the concentration found in the body must be sufficient to cause the adverse reaction or be beyond the expected therapeutic dose. In addition, the type of specimen collected must be one that will properly reflect the drug concentration in the body at the time of the incident/death. For these reasons, the interpretation of the drug’s reaction for the purposes of determination of cause and effect can be problematic. The method of sample analysis and a review of the laboratory data are of key importance. Test results have the potential for error, and may need to be critiqued by a qualified expert. Drug Injury: Liability, Analysis and Prevention,  Chapters 43, 44 (PDF)