Catatonia is a complication of bipolar disorder, which is a constellation of symptoms such as catalepsy, mutism, and stupor. Standard therapy for catatonia contains benzodiazepines and electroconvulsive therapy. An uncomplicated catatonia is usually a benign condition. On the other hand, malignant catatonia is a life-threatening condition that is complicated with fever, autonomic instability, delirium, and rigidity. The syndrome is typically fulminant and progresses rapidly within a few days without appropriate intervention. Several previous reports suggested that some catatonia are associated with the overstimulation of N-methyl-D-aspartate (NMDA) receptor, and that amantadine may have an effectiveness for catatonia, as a NMDA receptor antagonist. We report a case of successful treatment for malignant catatonia refractory to benzodiazepines, by using amantadine.

A 64-year-old Japanese woman with bipolar disorder was referred to our hospital because of 8-week prolonged fever. On admission, she was in febrile and stuporous states. Severe rigidity was observed in her extremities. Blood tests, lumbar puncture, and blood cultures were all negative. Brain MRI was normal. Consequently, we reached a diagnosis of malignant catatonia, and thus we gave additional benzodiazepines for her catatonic symptoms. However, there was no improvement, and we finally add a 50 mg/day amantadine for her malignant catatonic state.

Her fever resolved in a few days. Gradual dose-titration of amantadine led her clinical manifestation to completely disappeared.

Amantadine can be a potential option as one of the pharmacological therapies for refractory malignant catatonia.

The authors have not supplied their declaration of competing interest.