Trexol

MTX

Antineoplastic chemotherapy: Breast cancer, gestational choriocarcinoma, chorioadenoma destruens, hydatidiform mole. Palliation of acute & subacute lymphocytic, acute lymphoblastic (stem cell) & meningeal leukaemia. In combination w/ corticosteroids for maintenance of induced remissions. Monotherapy or in combination w/ other anticancer agents for osteogenic sarcoma, acute leukaemia, bronchogenic carcinoma, epidermoid head & neck carcinoma. Advanced stages (III & IV Peters Staging System) of lymphosarcoma in childn & mycosis fungoides. Psoriasis chemotherapy: Symptomatic control of severe, recalcitrant, disabling psoriasis inadequately responsive to other forms of therapy.

Breast carcinoma 40 mg/m² IV on day 1 & 8 only. Choriocarcinoma & similar trophoblastic diseases 15-30 mg daily IM for 5 days. Repeat 3-5 times as required w/ ≥1 wk rest period. Leukemia Induction: 3.3 mg/m² in combination w/ prednisolone 60 mg/m² daily for 4-6 wk. Maintenance: 30 mg/m² IM twice wkly or 2.5 mg/kg IV every 14 days. Meningeal leukemia ≥3 yr 12 mg, 2 yr 10 mg, 1 yr 8 mg, <1 yr 6 mg by intrathecal inj w/ 2-5 days intervals. Max: 15 mg single dose. Stages I-II Burkitt's tumour 10-25 mg daily for 4-8 days. Stage III lymphosarcomas 0.625-2.5 mg/kg daily. Mycosis fungoides 50 mg IM wkly or 25 mg IM twice wkly. Psoriasis chemotherapy Initial test dose: 5-10 mg 1 wk prior to initiation. Wkly single IM/IV dose schedule: 10-25 mg wkly. Not to exceed 50 mg wkly.

Hypersensitivity. Overt or lab evidence of immunodeficiency syndromes; preexisting blood dyscrasias eg, significant marrow hypoplasia, leukopenia, thrombocytopenia or anaemia. Severe (CrCl <30 mL/min) for MTX doses <100 mg/m² & moderate renal impairment (CrCl <60 mL/min) for MTX doses >100 mg/m². Pregnancy & lactation.

Discontinue use if significant drop in blood cell counts occur. Patients w/ preexisting bone marrow aplasia, leukopenia, thrombocytopenia or anaemia. Acute or chronic interstitial pneumonitis associated w/ blood eosinophilia, persistent cough or dyspnoea; pulmonary alveolar haemorrhage associated w/ vasculitis & other comorbidities; pulmonary symptoms, MTX-induced lung disease, possibility of Pneumocystis carinii pneumonia; pleural effusions & ascites, tumour lysis syndrome; immunosuppression. Assess history, physical exam & lab tests of renal & liver function & blood elements. Perform complete haemogram, haematocrit & urinalysis; chest X-ray. Monitor serum MTX level. High-dose & prolonged use. Not to be given concurrently w/ salicylates, sulphonamides, phenytoin, some antibacterials eg, tetracycline, chloramphenicol, PABA. Concomitant use w/ PPIs; folic acid-containing vit prep. May affect ability to drive & use machines. Renal dysfunction. May impair fertility. Men & women of childbearing potential should use effective contraception during & for 6 mth after treatment. Avoid use during pregnancy. 100 mg: Not to be used intrathecally.

Ulcerative stomatitis, leukopenia, nausea, abdominal distress.

Increased toxicity w/ salicylates, hypoglycaemics, diuretics, sulphonamides, diphenylhydantoins, tetracyclines, chloramphenicol, PABA, acidic anti-inflammatory agents. Avoid concomitant use w/ nephrotoxic or hepatotoxic potential eg, alcohol. Decreased effectiveness w/ folic acid-containing vit prep or derivatives. Reduced tubular secretion & enhanced fatal toxicity w/ NSAIDs, salicylates. Diminished renal tubular transport by probenecid, penicillins. Inhibited clearance w/ PPIs eg, omeprazole, pantoprazole. Severe bone marrow depression w/ co-trimoxazole or trimethoprim. Potentiated folate metabolism effect w/ nitrous oxide. Increased hepatitis risk w/ acitretin metabolite, etretinate. Increased bioavailability of mercaptopurine. Reduced theophylline clearance.

Disease-Modifying Anti-Rheumatic Drugs (DMARDs) / Cytotoxic Chemotherapy

L01BA01 - methotrexate ; Belongs to the class of antimetabolites, folic acid analogues. Used in the treatment of cancer.
L04AX03 - methotrexate ; Belongs to the class of other immunosuppressants.

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