Understanding and treating depression in anxious patients.

Depression is a common complication of anxiety disorders. Major depressive disorder may be the primary diagnosis, the patient having been unaware of depressed affect until anxiety became less prominent. Depression may also be a comorbid condition, appearing because anxiety lowers the threshold for its development or as a result of use of central nervous system depressants or intercurrent medical illnesses. Depression may also be a response to psychosocial consequences of anxiety or its resolution. In some anxious patients, depression is a later stage in the development of a dysregulated stress response. Initial treatment of depression involves therapy for organic causative factors and psychosocial problems. Medications that may be useful for both depression and anxiety include cyclic antidepressants, monoamine oxidase inhibitors, and possibly azapirones and benzodiazepines. Combined anxiolytic-antidepressant treatment may be necessary for some patients.