We retrospectively reviewed the clinical course and response to treatment of 67 
patients with tardive dystonia. The age at onset ranged from 13 to 72 years 
without predilection to any particular age group or sex. Patients developed 
tardive dystonia even after relatively short duration of exposure to dopamine 
antagonists (21% within one year). Five of 42 patients withdrawn from these 
drugs remitted. Overall clinical improvement occurred in 52% of patients. 
Tetrabenazine and reserpine were most effective (greater than 50% response rate) 
in controlling dystonia. Anticholinergic drugs diminished dystonia in 46% of 
patients.