The past decade has seen a proliferation of research and publication related to laboratory science and psychiatry. Those advances are now captured in this revised second edition of Laboratory Medicine in Psychiatry and Behavioral Science. Backed by years of clinical practice and research in neuropsychiatry and informed by literature from the National Library of Medicine as well as sources such as the American Society of Health-System Pharmacists Drug Information book, online resources from ARUP Laboratories, and the American Association for Clinical Chemistry, this volume is designed to assist psychiatrists and other behavioral health clinicians in the care of adult psychiatric patients across a wide range of settings. With the same comprehensive approach that was a hallmark of the first edition, this edition features new sections on COVID-19, 22q11.2 deletion syndrome, and DRESS syndrome, as well as updated descriptions of • Laboratory tests, from CT angiography and blood alcohol level to electrocardiograms and a renal function panel• Diseases and conditions, including Alzheimer's disease, autism spectrum disorder, HIV and AIDS, and schizophrenia• Screening and monitoring of psychotropic medications, including benzodiazepines, fluoxetine, naltrexone, and vardenafil Readers can be confident that the provided information is relevant to their daily practice: The included laboratory tests were chosen because they are core for any patient, are novel in medicine, or are particularly pertinent to psychiatry or behavioral health. Similarly, the diseases and conditions described are those for which laboratory tests are important in diagnosis or differential diagnosis; those that are common among psychiatric or geriatric patients; and those that have significant psychiatric, cognitive, or behavioral consequences. With appendixes that contain algorithms, tables, and figures that will aid in understanding and interpreting various laboratory tests and their underlying biology, this volume sets itself apart from any other reference and is an indispensable resource for anyone in general psychiatric practice, from trainees to physician assistants and advanced practice nurses.