Olanzapine-Induced Systemic Lupus Erythematosus: A Case Report

Abstract Olanzapine is a widely prescribed atypical antipsychotic, generally considered safe regarding hematological adverse effects compared to other antipsychotics. We report the case of a 19-year-old female treated for depression with fluoxetine 20 mg, who developed a clinical and biological picture suggestive of drug-induced systemic lupus erythematosus (SLE) following the introduction of olanzapine 5 mg for delusional symptoms. Thirty days after starting olanzapine, the patient presented with prolonged fever, fatigue, anorexia, polyarthralgia, and a scaly skin rash. Laboratory tests revealed anemia (hemoglobin 9 g/dL), severe leukopenia (1000/mm³), and positive antinuclear antibodies, while other specific antibodies remained negative. This case highlights the importance of considering drug-induced SLE in the presence of systemic manifestations in patients treated with olanzapine, even in the absence of classic specific SLE antibodies.