Anemia potentially caused by infections or tumors. Patients who receive repeated blood transfusions. Dark discolouration of faeces may occur. Reconsider treatment if therapy does not succeed (Hb increases by about 2-3 g/dL after 3 wk). Exclude possible vit B
12 deficiency in anemic patients prior to treatment due to risk of irreversible neurological disorders. Not recommended in childn & adolescents ≤12 yr. Elderly.