Life threatening neuroleptic malignant syndrome due to olanzapine

The frequency of neuroleptic malignant syndrome (NMS) after clozapine or olanzapine is low and often of non-serious nature. A 49 year-old female patient developed NMS 12 days after olanzapine re-exposure. Olanzapine was stopped, the patient was transferred to an ICU and received a course of nine uni- and bilateral ECT treatments. This led to remission. 14 months earlier the patient had presented with a first severe NMS episode after hal-, operidol depot injection and 4 days after starting oral clozapine. Following the first NMS episode olanzapine (20 mg per day) was administered for 11 months without adverse effects.