Catatonia is not schizophrenia: Kraepelin's error and the need to recognize catatonia as an independent syndrome in medical nomenclature.

Catatonia is a motor dysregulation syndrome described by Karl Kahlbaum in 1874. He understood catatonia as a disease of its own. Others quickly recognized it among diverse disorders, but Emil Kraepelin made it a linchpin of his concept of dementia praecox. Eugen Bleuler endorsed this singular association. During the 20th century, catatonia has been considered a type of schizophrenia. In the 1970s, American authors identified catatonia in patients with mania and depression, as a toxic response, and in general medical and neurologic illnesses. It was only occasionally found in patients with schizophrenia. When looked for, catatonia is found in 10% or more of acute psychiatric admissions. It is readily diagnosable, verifiable by a lorazepam challenge test, and rapidly treatable. Even in its most lethal forms, it responds to high doses of lorazepam or to electroconvulsive therapy. These treatments are not accepted for patients with schizophrenia. Prompt recognition and treatment saves lives. It is time to place catatonia into its own home in the psychiatric classification.