Affective disorders and tardive dyskinesia

Evidence from multiple lines of study indicate that mood disorders, particularly depression, are a risk factor for developing tardive dyskinesia (TD). Important patient and treatment factors include: 1) frequent retrospective rediagnosis of affective disorders instead of schizophrenia when the long-term course of illness and response is evaluated, and 2) TD onset after relatively brief (few months to few years) exposure to low to moderate neuroleptic doses. Mechanisms underlying this increased sensitivity to TD are unknown. It has been hypothesized that the cyclic mono- and catecholamine activity during mood changes makes the brain more vulnerable to the direct neuroleptic effects or the compensatory processes initiated by these drugs. There may also be an interaction between neuroleptic drugs and antidepressant agents which produce greater vulnerability to TD. Additionally, neuroleptic drug use may be different in affective disorders, such as high doses for short time periods with mania. Treating TD in patients with mood disorders is often difficult. The psychiatric diagnosis should be the first priority in treatment regimens. Then, strategies for addressing TD should be considered. Occasionally lithium and/or antidepressants may be effective in treating both affective disorders and TD in some patients. Specific drug therapies for TD have not been consistently effective. Therefore, the passage of time may be the best treatment approach. Preventing TD should receive the highest priority. In the short term, neuroleptic drugs should be limited to managing acute psychotic symptoms in patients with mood disorders. In the long term, neuroleptics should be reserved for manic or depressive symptoms that do not respond to standard therapy. The overall goal is to use the lowest effective neuroleptic dose for the shortest period of time in patients who benefit from these valuable drug treatments.