Acute exacerbation of psychiatric symptoms during influenza treatment with oseltamivir in chronic schizophrenia

Influenza treatment and prophylaxis with oseltamivir are critically important in reducing the morbidity and mortality of patients in chronic psychiatric facilities. Abnormal behavior, delusions, perceptual disturbances, mania, and depression have all been reported as oseltamivir-related psychiatric side effects. We hereby report two chronic schizophrenia patients in Taiwan manifesting psychiatric instability who were being treated with oseltamivir for suspected influenza infection, and further discuss other potential contributing factors. The possibility that oseltamivir can cause psychotic or affective symptoms suggests that additional caution is necessary for its use in patients with an established psychiatric diagnosis.