Olanzapine-induced de novo type 2 diabetes mellitus with acute kidney injury in an autistic female: A case report

Olanzapine, a second-generation antipsychotic widely used in psychotic and autism spectrum disorders, is associated with significant metabolic side effects including hyperglycemia, dyslipidemia and weight gain. We present a rare case of olanzapine-induced de novo type 2 diabetes mellitus (DM) complicated by acute kidney injury (AKI) in a young female with autism. A 31-year-old female with a known history of autism spectrum disorder on long-term olanzapine (10 mg/day) presented with a recent fall, decreased urine output, poor appetite and generalised weakness. Laboratory evaluation revealed severe hyperglycaemia (GRBS 600 mg/dl), elevated HbA1c (9.8%) and serum creatinine (5.9 mg/dl), confirming acute kidney injury secondary to uncontrolled hyperglycaemia. Olanzapine was discontinued upon suspicion of drug-induced metabolic dysregulation. The patient was managed with insulin therapy, haemodialysis, intravenous antibiotics and fluid management. Risperidone (2 mg/day) was initiated for behavioural control. Gradual improvement was observed in glycemic profile, renal function and overall clinical status over 12 days. Early recognition and drug discontinuation are critical in preventing irreversible metabolic and renal damage. Substituting lower-risk agents such as risperidone can maintain psychiatric stability while minimising metabolic burden. This case underscores the importance of baseline and periodic metabolic screening in patients receiving atypical antipsychotics. Clinicians should remain vigilant for symptoms of hyperglycaemia or renal dysfunction. Prompt withdrawal of olanzapine and initiation of insulin therapy can reverse metabolic derangements effectively.