This fourth edition of the classic, best-selling textbook-ideal for the classroom and the reference shelf-includes a new section on "special topics" in forensic toxicology and updated chapters on drug testing, methods validation, alcohol, GHB, and metals. Since the publication of the first edition in 1999, Principles of Forensic Toxicology has been used extensively for teaching students taking a one-semester course in forensic toxicology. It has also proven to be an invaluable reference for laboratorians. The first section provides an introduction to postmortem forensic toxicology, human performance forensic toxicology, forensic drug testing, and pharmacokinetics and pharmacodynamics. Additions to this section of the fourth edition include chapters on pain management and performance-enhanced drug testing. The second section is devoted to analytical principles, including both theory and applications. Methodologies covered include specimen preparation, spectrophotometry, chromatography, immunoassay, mass spectrometry, and methods validation. The third section covers commonly encountered analytes, including alcohol, benzodiazepines, GHB, miscellaneous central nervous system depressants, opioids, cocaine, cannabis, amphetamines/sympathomimetic amines, hallucinogens, anticonvulsants, antiarrhythmics, antidepressants, antihistamines, neuroleptics, nonnarcotic analgesics, carbon monoxide/cyanide, inhalants, and metals. The newly added fourth section includes chapters on in vitro stability of drugs, postmortem redistribution, postmortem chemistry, pharmacogenomics, hair, and meconium.