Catatonic syndrome following recovery from neuroleptic malignant syndrome

In June 1992, a 51-year-old Caucasian man with a mild learning disability was prescribed chlorpromazine and thioridazine for sleeplessness and agitation. He developed neuroleptic malignant syndrome (NMS) which was treated successfully with intravenous diazepam. Without further exposure to neuroleptics, the patient became acutely unwell with signs of catatonic syndrome in March 1993 and responded to oral diazepam. When the dose of diazepam was reduced in August 1993, the catatonic syndrome recurred and responded to an increase in his oral diazepam. In the past, the patient had been admitted to hospital in 1983 and 1986 with severe extrapyramidal symptoms and parkinsonism following prescription of neuroleptics for agitation. This case provides evidence that patients with a predisposition to catatonic syndrome may be at increased risk of developing NMS, and therefore, should not be treated with neuroleptics.