Includes bibliographical references.

An introduction to tests performed in toxicology laboratories and methodologies available for such testings -- Challenges in drugs of abuse testing -- False positive results in immunoassays for drugs of abuse testing -- True positive drugs of abuse test results due to prescription and non-prescription drugs -- When toxicology report is negative in a suspected overdosed patient : the world of designer drugs -- Abuse of magic mushroom, peyote cactus and solvent : no readily available laboratory tests -- False positive alcohol tests using breath analyzers and automated analyzers -- Role of laboratory in detecting other poisoning including pesticides, ethylene glycol, and methanol -- Poisoning with warfarin and superwarfarin : what laboratory can do? -- Plant poisoning and clinical laboratory -- Sources of erroneous results in therapeutic drug monitoring due to pre-analytical errors, high bilirubin, hemolysis, and heterophilic antibody -- Interferences in immunoassays used for digoxin monitoring -- Interferences in immunoassays used for monitoring anticonvulsants and usefulness of monitoring free anticonvulsants in certain patients -- Interferences in immunoassays used for monitoring tricyclic antidepressant -- Therapeutic drug monitoring of immunosuppressant drugs : limitations of immunoassays and need for chromatographic methods -- Effect of drug-herb interactions on therapeutic drug monitoring -- Pharmacogenomics and toxicology laboratory -- Approaches for eliminating interference/discordant specimen in therapeutic drug monitoring and drugs of abuse testing.