Book excerpt: The Textbook of Medical Psychiatry was written for the wide range of clinicians who grapple with the diagnostic and treatment challenges inherent in this clinical reality: medical and psychiatric illnesses do not occur in isolation from one another. Because assessment in these cases may be challenging, the book addresses general medical conditions that directly cause psychiatric illness and the medical differential diagnosis of common psychiatric illnesses. In addition, the book describes how the presentation and treatment of both psychiatric and medical disorders are modified by the presence of comorbid conditions. The editors, who are at the forefront of the field, have assembled an outstanding group of contributors, all of whom share the objective of helping psychiatrists, internists, neurologists, trainees, and other health care providers recognize the medical issues facing patients with psychiatric symptoms, and vice versa. Proper assessment and treatment are dependent on the skillful application of this knowledge. Written in down-to-earth, clinically grounded prose, this text Provides a comprehensive exploration of approaches to the patient, including perspectives from internists and neurologists on dealing with diagnostic uncertainty and special chapters on the neurological examination, cognitive testing, neuroimaging, laboratory testing, and toxicological syndromes. Presents a review of medical disorders that can directly or indirectly affect the clinical presentation and course of psychiatric disorders. Presents a review of psychiatric disorders that can be caused by medical illnesses or affect the clinical presentation and course of medical disorders. Includes chapters on pain, insomnia, and somatoform disorders, conditions that accompany many psychiatric and medical illnesses and that fall in the boundary between these practice settings. In clinics and offices every day, physicians encounter patients whose presentations are atypical or whose symptoms are not responsive to usual care. When facing the challenges of accurately assessing complicated symptoms and managing the care of complex patients, clinicians often seek advice from colleagues whose perspectives and expertise they trust. The chapters in the Textbook of Medical Psychiatry can be consulted in much the same fashion, expanding clinicians' knowledge base and helping them to more effectively diagnose and care for their patients.