Methotrexate reference guide for safe and effective use from the American Society of Health-System Pharmacists (AHFS DI). Methotrexate is an antimetabolite used in the treatment of certain neoplastic diseases, psoriasis and rheumatoid arthritis. In combination with other chemotherapeutic agents, high dose methotrexate doses followed by leucovorin rescue may be effective in prolonging relapse-free survival in patients with non-metastatic osteosarcoma. Methotrexate. Notes: In patients older than 40 years of age, consider using cisplatin and doxorubicin without high dose methotrexate. Drug status: All drugs in this protocol are on the PBS general schedule Methotrexate is contraindicated in pregnancy in women who are being treated for nonmalignant diseases (e.g., psoriasis, rheumatoid arthritis, polyarticular juvenile idiopathic arthritis). Methotrexate (MTX), formerly known as amethopterin, is a chemotherapy agent and immune system suppressant. It is used to treat cancer, autoimmune diseases, ectopic pregnancy, and for medical abortions. Types of cancers it is used for include breast cancer, leukemia, lung cancer, lymphoma, and osteosarcoma. Types of autoimmune diseases it is. INTRODUCTION. Folate antagonists were among the first antineoplastic agents to be developed. In 1948, aminopterin was used to induce remission in childhood acute lymphoblastic leukemia (ALL), and the related agent methotrexate (MTX) is still an important component of modern treatment for ALL as well as a number of other hematologic malignancies. Progression on previous high dose methotrexate Serum creatinine greater than 150 micromol/L or estimated creatinine clearance less than 60 mL/min: Methotrexate Injection, USP (Contains Preservative) Rx only WARNINGS FOR INTRATHECAL AND HIGH-DOSE THERAPY, USE THE PRESERVATIVE-FREE FORMULATION OF METHOTREXATE. A 36-year-old woman was hospitalized for preoperative chemotherapy for osteosarcoma. She received intravenous fluids for 12 hours for volume expansion, then methotrexate 24 g (12 g/m2) over 6 hours. This was followed by intravenous leucovorin 200 mg Methotrexate is indicated in the treatment of gestational choriocarcinoma, chorioadenoma destruens, and hydatidiform mole. In acute lymphocytic leukemia, methotrexate is indicated in the prophylaxis of meningeal leukemia and is used in maintenance therapy in combination with other chemotherapeutic agents.