Mercaptopurine

Adults: Crohn's disease Adults: Start with 1 to 1.5 mg/kg daily. The dose may be increased to 125 mg daily. Children: Start with 1 to 1.5 mg/kg daily. The dose may be increased to a maximum of 75 mg daily. Acute lymphocytic leukaemia Adults: The usual maintenance dose starts at 1.5 to 2.5 mg/kg daily, taken as a single dose, and is usually given in combination with methotrexate. The dose may vary from person to person depending on response and tolerance. Blood counts should be checked at least once a week. Treatment must be stopped immediately if there is a sharp drop in the white cell count or severe bone marrow depression. Treatment may be restarted slowly and carefully once the white cell count has stayed steady for 2 to 3 days or has begun to rise. The dose should be reduced when used together with allopurinol. Children: The usual maintenance dose starts at 1.5 to 2.5 mg/kg daily, taken as a single dose, and is usually given in combination with methotrexate. The dose may vary from child to child depending on response and tolerance. Blood counts should be checked at least once a week. Treatment must be stopped immediately if there is a sharp drop in the white cell count or severe bone marrow depression. Treatment may be restarted slowly and carefully once the white cell count has stayed steady for 2 to 3 days or has begun to rise. The dose should be reduced when used together with allopurinol.