Olanzapine and the Spectrum of Drug-induced Diabetes: Unveiling Dual Risk Factors for Type 2 Diabetes and Acute-onset Ketoacidosis

Olanzapine, a widely prescribed atypical antipsychotic, is associated with significant metabolic side effects including hyperglycemia and new-onset diabetes mellitus. While it often contributes to or mimic conventional type 2 diabetes through weight gain and insulin resistance, olanzapine can also induce a distinct, acute, ketosis-prone form of diabetes characterized by acute, severe hyperglycemia, and a high risk of diabetic ketoacidosis (DKA). This review summarizes the current understanding of olanzapine's multifaceted diabetogenic mechanisms, distinguishing its contributions to both type 2 diabetes and this severe drug-induced presentation, and emphasizes the critical implications for patient management, particularly concerning the acute manifestations of DKA. We also discuss its unique position within the broader classification of other types of diabetes and drug-induced etiologies.