RT Journal Article SR Electronic T1 Delayed-Onset olanzapine-induced rhabdomyolysis JF BMJ Case Reports JO BMJ Case Reports FD BMJ Publishing Group Ltd SP e254377 DO 10.1136/bcr-2022-254377 VO 16 IS 3 A1 Jun Hua Bowen Lim A1 Billy Robinson A1 Judith Savige YR 2023 UL http://casereports.bmj.com/content/16/3/e254377.abstract AB Olanzapine is a commonly used and effective second-generation antipsychotic agent used for the control of paranoia and agitation in schizophrenia and bipolar disorder as well as in the behavioural and psychological symptoms of dementia. Serious side effects of treatment are uncommon but spontaneous rhabdomyolysis represents a rare complication. We describe here a patient treated with a stable dose of olanzapine for more than 8 years who developed acute severe rhabdomyolysis without an identifiable trigger and without features suggestive of neuroleptic malignant syndrome. The rhabdomyolysis was atypical in its delayed onset and severity with a creatine kinase level of 345 125 U/L, the highest level reported in the available literature. We also describe the clinical manifestations of delayed-onset olanzapine-induced rhabdomyolysis and its differentiation from neuroleptic malignancy syndrome, and we highlight key aspects of management to prevent or minimise further complications such as acute kidney injury.