Abstract
A 63-year-old male patient with a history of bipolar I disorder presented to the emergency department in an acutely psychotic state. The patient had just returned from vacation in a malarial high-risk area and, as a result, had taken five weekly doses of mefloquine for prophylaxis. The patient's bipolar disorder was being treated with lithium, and he had been stable for about 8 years. All organic causes of psychosis were ruled out. The patient was admitted to the inpatient psychiatric unit and was treated with quetiapine until he was stable enough to return home.