Neuroleptic Malignant Syndrome (NMS) is a rare and potentially lethal adverse reaction generally associated with typical antipsychotics. Cardinal features include muscle rigidity, hyperthermia, mental status changes, elevated CPK levels.

We report on a patient receiving olanzapine, an atypical antipsychotic, who developed NMS.

A 31 year-old male with a 5 year history of paranoid psychosis, was successfully treated with olanzapine 15 mg per day. He was also receiving oxcarbazepine for epilepsy (1200 mg/ day) and also suffered from spastic congenital paraparesis. He was almost asymptomatic for 4 years. At some point there was a recurrence of his illness with restlessness and aggressive behaviour. The patient decided to receive additionally 5 mg of olanzapine,without consulting psychiatrist. Soon he developed hyperthermia, hypertonia and confusion. He was initially admitted in a general hospital with leukocytosis and elevated CPK levels (1999 U/L). Other laboratory examinations were within normal limits. He was treated with ceftriaxone and parenteric fluids. After 48 hours he was improved and olanzapine was reinitiated (10 mg/day), and a few hours later he developed fever (40' C), hypertonia, dysphagia, confusion, CGS: 7/15 and elevated CPK levels (4900 U/LT). He was then transferred to the Intensive Care Unit and received treatment for NMS with bromocryptine and dantrolene sodium. His temperature returned to normal in two days and in 6 days he was physically stable. Twenty days later he received treatment for psychosis with low dose quetiapine.

NMS characterized by muscular rigidity and fever may rarely occur with atypical neuroleptics, such as olanzapine.