This May marked the 50th anniversary of Kaplan & Sadock’s Comprehensive Textbook of Psychiatry, the gold-standard reference for clinicians in training and seasoned professionals alike. Over the years, the seminal tome has grown from 600 pages to more than 5,000 pages in 2 volumes, drawing on 650 experts in the mental health field. We caught up with NYU School of Medicine co-editors Benjamin J. Sadock, MD, the Menas S. Gregory Professor of Psychiatry, and his wife, Virginia A. Sadock, MD, professor of psychiatry, to discuss the book, now in its 10th edition, and the milestone. The book’s other co-editor is Pedro Ruiz, MD, professor of psychiatry at Baylor College of Medicine.

The latest edition weighs 25 pounds. Has it always been so expansive?

Dr. Benjamin Sadock: Yes. The original concept was brought to several major medical publishers, all of whom turned it down. There were so many schools of thought back then that they feared getting a large group of psychiatrists to agree would be like herding cats. But we got people to work together and express their points of view without attacking each other. Our contributors write whatever they want and are never censored. If they take issue with a concept or declare, “This drug shouldn’t be used,” we encourage them to say it. Our goal is to improve and maintain the professional competence of practitioners.

What has been the biggest shift in psychiatry since you began this project?

Dr. Benjamin Sadock: Over the past 25 years, we’ve witnessed a pharmacologic revolution due to the vast array of drugs developed to treat all types of mental disorders. It’s crucial, however, that drugs not supplant psychotherapy. The doctor–patient relationship is the cornerstone of psychiatry, and drug therapy combined with psychotherapy has been found to be more effective than either used alone. Words matter.

They can damage the brain, but they can also heal the brain. A second revolution is called neuroregulation, in which pulses of electricity are delivered to specific areas of the brain to help patients with obsessive–compulsive disorder and major depression. Although the science is in its infancy, it holds great promise for advancing our field.

Which topics in this edition are new or extensively updated?

Dr. Virginia Sadock: One new section is transgender identity disorder, which has undergone many conceptual changes. Most children have a pretty solid gender identity as early as two or three years of age. But in some people, there is confusion, a dissonance. A transgender person is saying, “You may look at me and see a woman, but inside I’m a man.” Or vice versa. We now know that gender identity is not black and white—it’s a spectrum. Our approach to therapy has become much more nuanced.

Dr. Benjamin Sadock: As our population ages, psychiatrists are getting much more involved with end-of-life issues. Several areas of the text cover the experimental use of some hallucinogenic drugs to treat patients who are dying, suicidal, or addicted to substances such as cocaine, alcohol, or opioids.

We also added a chapter on caring for the caregivers of patients with dementia. They bear a tremendous burden, and psychiatry has much to offer them.

What’s on the horizon for your field?

Dr. Benjamin Sadock: In 50 years of editing this textbook, we know as little about the cause of schizophrenia now as we did when we started. But things are beginning to change. If we can understand how the 100 billion neurons in the brain connect—or don’t—we can potentially influence them to find a cure. We can finally do more than just treat the symptoms. Neuroscience is the future of psychiatry.