Monitoring human exposure to drugs and chemicals via measurement of the agents themselves, their biotransformation products or their biomarkers in biological specimens has never held more significance than it does today. The numerous applications of such appraisals include therapeutic drug monitoring, emergency toxicology, employee drug screening, clinical diagnosis of disease, industrial chemical exposure, assessment of ecocontaminant absorption, drug-facilitated sexual assault, criminal poisoning and investigation of sudden or unexpected death. This book is dedicated to providing the essential information needed to launch a search for suspect agents by delineating the fate in the human body of the most commonly encountered substances. In this current edition, we have added over 280 drugs and chemicals, bringing the total coverage to more than 2000 substances.The single volume format and the page count were maintained by slightly increasing the text line length and reducing the citation font size. The new entries include amino acids (leucine, tyrosine), anabolic steroids (clostebol, methisterone), amphetamine derivatives (ethylamphetamine, 4-fluoroamphetamine), antibiotics (bleomycin, pefloxacin), antineoplastic agents (niraparib, volasartib), antipsychotic agents (benperidol, prothipendyl), antiviral agents (grazoprevir, trifluridine), benzodiazepines (metizolam, nimetazepam), bronchodilators (doxofylline, procaterol), dietary supplements (hydroxycitric acid, tyrosine), fentanyl analogues (fluorofentanyl, ocfentanil), hormones (histamine, vasopressin), hypoglycemic agents (ertugliflozin, gemigliptin), performance enhancers (ipamorelin, hexarelin), pesticides (metolachlor, permethrin), plant poisons (aristolochic acid, coniine), shellfish poisons (brevetoxin, domoic acid), street drugs (desomorphine, 3-methoxyphencyclidine), synthetic cannabinoids (AMB-FUBINACA, MEPIRAPIM), synthetic cathinones (clephedrone, mexedrone) and vitamins (folic acid, pyridoxine).