Overview of severe mental illness.

The severe mental illnesses are psychiatric disorders characterized by their persistence and extensive disability. Classification of these disorders has seen improved reliability, but problems remain with validity. Etiological formulations emphasize the biological origins of the disorders, but psychological factors, chiefly in the area of stress, are recognized as important in the management of relapse. Psychological features, especially those apparent during psychotic episodes, make the disorders particularly difficult to treat. Patients tend to be noncompliant. In addition, these features dispose people with severe mental illnesses to behaviors that place them at risk for HIV and other catastrophic illnesses. New psychopharmacological treatments may improve compliance and reduce relapse, but none has made psychosocial treatments unnecessary. Progress in developing effective treatments has been slow, but prospects are encouraging.