Considering the patient’s RS ≥ 15%, SF3B1 negativity, absence of clonal characteristics in the hematopoietic system, nadir Hb level of 37 g/L, coupled with a clear drug-related cause and significant improvement following drug withdrawal, the diagnosis of severe acquired sideroblastic anemia induced by the combined use of olanzapine and fluvoxamine was established. The gene discussed is GSTM1; the disease is sideroblastic anemia.