Ziprasidone-Induced Acute Dystonia

Mr. A, a 53-year-old man, was admitted to the inpatient psychiatry unit with a diagnosis of schizophrenia, paranoid type. He came to the Department of Veterans Affairs emergency room complaining of increased intrusiveness of auditory hallucinations and ideas of reference. Old charts revealed that his illness had been managed with oral risperidone, 3 mg b.i.d., for 3 years. Benztropine was prescribed for trismus during this interval. His risperidone dose was then decreased to 2 oral mg b.i.d., and an anticholinergic was no longer required. For 3 months before admission, Mr. A had traveled through several states and received no known antipsychotics.

Upon admission, the results of a comprehensive metabolic panel were found to be within normal limits, and a complete medical history and physical examination revealed a man without general medical conditions. He received oral ziprasidone, 40 mg b.i.d., for 1 day then 80 oral mg b.i.d.

Five 80-mg doses were given without untoward effects. Four hours after the sixth dose, Mr. A was in distress. He demonstrated a notable torticollis and dystonic posturing of his left carpus. Palpation of his musculature revealed spasm. Intramuscular diphenhydramine, 50 mg, was given, and contraction of his muscles was alleviated within minutes. Mr. A was observed for approximately 24 hours without reoccurrence and finally left the unit against medical advice and refused trials with other medications.