[Malignant syndrome caused by a combination of bromperidol and donepezil hydrochloride in a patient with probable dementia with Lewy bodies].

The patient was a 68-year-old man with a 1-year history of delusions related to well-formed and detailed visual hallucinations. Bromperidol 12 mg was prescribed to treat his symptoms. After a diagnosis of dementia of Alzheimer's type was suspected, the patient received donepezil hydrochloride 5 mg. One week later, the patient's Parkinsonism deteriorated. One month later, the patient developed radical edema of the eyelids and the anterior neck, hypoproteinemia, and severe anteflexion of the body. One and a half months later, the patient developed malignant syndrome. His medication was discontinued and parenteral nutrition was started. The patient recovered from his malignant syndrome. However, 1 month later, his Parkinsonism had not improved. The patient received levodopa to treat his Parkinsonism and his symptoms subsequently improved. The hallucinations and systematized delusions returned. The patient's cognitive impairment deteriorated on one side. The aggravation of extrapyramidal symptoms and the development of malignant syndrome were believed to have been caused by the combination of bromperidol and donepezil hydrochloride and poor nutrition. Caution should be exercised when prescribing an antipsychotic drugs with donepezil hydrochloride.