title: Olanzapine overdose is associated with acute muscle toxicity.
abstract: Olanzapine is an atypical antipsychotic that is reported to cause myopathy and raised creatine kinase (CK) levels. The prevalence and severity of acute myopathy after deliberate olanzapine ingestion are unclear. Therefore, we reviewed case notes from 64 consecutive patients admitted to our institution after olanzapine overdose. Overall, serum CK was higher than five times the upper limit of normal in 17% of patients. The prevalence of raised CK values was positively correlated with the stated quantity of olanzapine ingested, suggesting a dose-dependent relationship for acute muscle toxicity. There was an apparent delay of 12 hours or more between olanzapine ingestion and the occurrence of maximum CK. Despite the high prevalence of acute muscle toxicity after olanzapine ingestion, none of the patients developed renal failure.
authors.affiliation: Scottish Poisons Information Bureau, Royal Infirmary of Edinburgh, Edinburgh, UK. stephen.waring@ed.ac.uk
authors.forename: W S
authors.initials: WS
authors.lastname: Waring
authors.forename: J
authors.initials: J
authors.lastname: Wrate
authors.forename: D N
authors.initials: DN
authors.lastname: Bateman
mesh_terms: D000208:Acute Disease; D000328:Adult; D014150:Antipsychotic Agents / Q000506:poisoning*; D001569:Benzodiazepines / Q000506:poisoning; D052283:Creatine Kinase, MM Form / Q000097:blood; D004305:Dose-Response Relationship, Drug; D062787:Drug Overdose; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000187:drug effects*; D009135:Muscular Diseases / Q000139:chemically induced; D000077152:Olanzapine; D012189:Retrospective Studies; D012206:Rhabdomyolysis / Q000097:blood / Q000139:chemically induced*; D012606:Scotland
chemical_list: D014150:Antipsychotic Agents; D001569:Benzodiazepines; D052283:Creatine Kinase, MM Form; D000077152:Olanzapine