Composition
Tab 2.5 mg/10 mg: Methotrexate 2.5 mg/10 mg. Inj 5 mg/50 mg/ 500 mg/1 gm: Methotrexate 5 mg/50 mg/500 mg/1 gm; vial.
Indications & Dosage
Antineoplastic; Buricitts Lymphoma Stages I & II: ORAL: Adults: 10-25 mg/day for 4-8 day for several courses; separate by 7-10 day rest period. Antineoplastic; Buricitts Lymphoma: Stage III: ORAL: Adult: 0.625-2.5 mg/kg/day. Leukaemia: Induction: 3.3 mg/m2 with prednisone every day. Remission maintenance: 15 mg/m2Orally/IM twice wkly or 2.5 mg/kg IV every 14 day. Mycosis fungoides: 5-50 mg every week, If poor response, increase to 15-37.5 mg twice weekly. Osteosarcoma: BY IV INJ: Initially 12 gm./m2, increase to 15 gm/m2 if peak levels of 1000 micro-molar not reached at end of INF. Choriocarcinoma, trophoblastic diseases: ORAL OR BY IM: 1530 mg every day x 5 day, rest for at leaset1 wk& repeat 3-5 times. Meningeal leukaemias: BY INTRATHECAL INJ: Children3 yr: 12 mg. 2 yr: 10 mg. 1 yr: 8 mg. <1 yr: 6 mg. Dilute preservative free Methotrexate to 1 mg/ml, dose every 2-5 day. Rheumatoid arthritis: Adults: Initially 7.5 mg once weekly or 2.5 mg every 12 hr x 3 doses once weekly. Max: 20 mg/week. Reduce to lowest effective dose. Juvenile rheumatoid arthritis: Children 2-16 yr: 10mg/m2once weekly, adjust dose to optimal response. Psoriasis: ORAL OR BY IV OR IM: Adults: Usual: 10-25 mg/week until adequate response achieved or use 2.5 mg every 12 hr x 3 doses, may increase gradually. Max: 30 mg/wk.
Administration
It may be administered IM, IV or IT. IV administration may be slow push, short bolus infusion or 24-42 hour continuous infusion. Dilute powder with D5W or NS to a concentration of 25 mg/ml (20 mg and 50 mg vials) and 50 mg/ml (1 gm vial). Intrathecal solutions may be reconstituted to 2.5 to 5 mg/ml with NS, D5W, LR or Elliotts B solution. Use preservative free preparations for IT or high dose administration.
Stability
Store at 20C-25C (68F-77F); excursions are permitted to 15C -30C (59F-86F). Protect from light.
Contraindications
Severe renal or hepatic impairment, Active infectious disease, immune deficiency syndrome, serious anaemia, leukopenia, thrombocytopenia, AIDS, pre-existing blood dyscrasias.
Precautions
Hematological depression, chronic hepatic disease, psychiatric disorder, elderly, Perform blood, urine, hepatic and renal test. Risk of pneumonitis, patient should report the symptoms of dyspnoea, cough and fever. Acute porphyrias, photosensitivity; psoriasis lesions aggravated by UV radiation (skin ulceration reported), diarrhoea, extreme caution in blood disorders (avoid if severe), peptic ulceration, risk of accumulation in pleural effusion or ascites; drain before treatment, ulcerative colitis, ulcerative stomatitis
Interactions
Protein bound drugs, alcohol, live vaccine, folic acid, folate antagonist, anticonvulsants, NSAIDs, cyclosporin, mercaptopurine, proton pump inhibitors, theophylline
Pregnancy
Contraindicated in pregnancy.
Lactation
Contraindicated. Discontinue breast-feeding
Side Effects
Alopecia, anaphylactic reactions, anorexia, arthralgia, blood disorders, changes in nail & skin pigmentation, chills, chronic pulmonary fibrosis, confusion, conjunctivitis, cystitis, diarrhoea, drowsiness, dyspepsia, dysuria, ecchymosis, furuncolosis, GI bleeding & ulceration, haematuria, hepatotoxicity, hypotension, impotence, interstitial pneumonitis, malaise, menstrual disturbances, mucositis, myalgia, myelosuppression, nausea, neurotoxicity, osteoporosis, paraesthesia, pericardial tamponade, pericarditis, photosensitivity, pleuritic pain, precipitation of diabetes, pruritus, pulmonary fibrosis, pulmonary oedema, rash, renal failure, Stevens-Johnson syndrome, telangiectasia, thrombosis, toxic epidermal necrolysis, toxic megacolon, urticaria, vaginitis, vasculitis, visual disturbance, vomiting. Rare: Pneumonitis