CALCIUM FOLINATE USP is used as an antidote against trimethoprim, methotrexate and pyrimethamine. It is used in the treatment of megaloblastic anemia related to pregnancy, sprue, infancy, nutritional deficiency. It is used in conjunction with fluorouracil or methotrexate at a high dose, to treat head and neck squamous cell carcinoma. Moreover, combination of this one and high dose of methotrexate, is used against gestational trophoblastic neoplasm.