The Diagnostic and Statistical Manual of Mental Disorders (DSM) is published by the American Psychiatric Association. The DSM provides a common language and standard criteria for the classification of mental disorders, which is used in the United States and to some extent internationally, by clinicians, researchers, psychiatric drug regulation agencies, health insurance companies, pharmaceutical companies, and policy makers. The DSM is produced by a panel of psychiatrists, many of whom have financial ties to the pharmaceutical industry. It is considered the “bible” of American psychiatry. The latest edition — DSM-IV — was published in 1994.

In 1952, the DSM was a small, spiral-bound handbook (DSM-I), but the latest edition (DSM-IV), is a 943-page magnum opus. Over time, psychiatric diagnoses have increased in the American population and in turn, drugs that affect mental states are then used to treat them. The theory that psychiatric conditions are caused by a biochemical imbalance is often used as a justification for their widespread use, even though the theory in unproven. Since there are no objective tests for mental illness and what is normal and abnormal is often unclear, psychiatry is a particularly fertile field for creating new diagnoses or broadening old ones.