The diagnosis and treatment of tardive disorders

Drugs that block dopamine receptors (dopamine receptor blocking agents; DRBA) may cause a variety of movement disorder syndromes. Among these syndromes are the tardive disorders, which are characterized by an onset weeks to years after the start of DRBA therapy and persist or even worsen after DRBA discontinuation. The tardive disorders may sometimes be permanent. The most common tardive disorders are oral-buccal-lingual dyskinesia, tardive dystonia, and tardive akathisia. The clinical characteristics and treatment of these syndromes are reviewed. Initial evaluation of a patient with a tardive disorder should focus on whether the offending DRBA may be discontinued, and whether the symptoms are severe enough to warrant symptomatic therapy. If it is necessary to continue antipsychotic therapy, consideration should be given to the novel antipsychotic clozapine, which does not cause tardive syndromes and may even ameliorate them. In general, the dopamine depletors reserpine and tetrabenazine are the most effective agents in the symptomatic treatment of the tardive syndromes. Other medications used in the treatment of the tardive syndromes are also reviewed.