A case of neuroleptic malignant syndrome successfully treated with amantadine

A paranoid schizophrenic patient developed the neuroleptic malignant syndrome after receiving three doses of fluphenazine HCl and two doses of thioridazine while he was recovering from major trauma. Treatment with diphenhydramine and benztropine mesylate was ineffective. Administration of amantadine HCl resulted in resolution of all symptoms within 24 hours. After 2 days, the amantadine was discontinued. The following day, the neuroleptic malignant syndrome appeared. Readministration of amantadine again resulted in prompt remission of symptoms.