Indications |
Oral Burkitt's lymphoma Adult: 10-25 mg daily for 4-8 days, repeated after 7-10 days.
Oral Acute lymphoblastic leukaemia Adult: Maintenance: 15 mg/m2 once or twice wkly, with other agents.
Oral Choriocarcinoma Adult: 15-30 mg daily for 5 days, repeat after an interval of ≥1 wk for 3-5 courses.
Oral Mycosis fungoides Adult: 2.5-10 mg daily to induce remission.
Oral Psoriasis Adult: 10-25 mg wkly as a single dose, adjust subsequent doses based on response.
Oral Rheumatoid arthritis Adult: 7.5 mg once wkly, adjust by response. Not more than 20 mg/wk.
Oral Crohn's disease Adult: 12.5-22.5 mg once wkly for up to 1 yr.
Intrathecal Meningeal leukaemia Adult: 12 mg/m2 (max 15 mg) once wkly for 2-3 wk, then once mthly. Alternatively, 200-500 mcg/kg every 2-5 day until CSF cell count is normalised. Child: <1 yr: 6 mg, 1 yr: 8 mg, 2 yr: 10 mg, >3 yr: 12 mg. Patients <3 yr should be treated in accordance with combination chemotherapy protocols. Admin is at wkly intervals and repeated until the CSF cell count is normal.
Intravenous Osteosarcoma Adult: Initial recommended dose: 12 g/m2 as a 4-hr infusion, followed by folinic acid, as part of combined therapy. May increase dose to 15 g/m2 in subsequent treatments if initial dosage is insufficient to achieve peak serum methotrexate levels of 454 mcg/mL at the end of the infusion. Methotrexate infusion is administered on postoperative wk 4, 5, 6, 7, 11, 12, 15, 16, 29, 30, 44 and 45; in combination with other chemotherapy agents. Folinic acid can be given orally, IM or IV inj starting 24 hr after the beginning of the methotrexate infusion. Give via parenteral routes If patient experiences GI toxicity (e.g., nausea, vomiting). Usual dosage of folinic acid: 15 mg every 6 hr for a total of 60 hr or a total of 10 doses.
Intramuscular Choriocarcinoma Adult: 15-30 mg daily for 5 days. Repeat after at least 1 wk for 3-5 courses. Alternatively, 0.25-1 mg/kg (max: 60 mg) every 48 hr for 4 doses followed by folinic acid rescue, repeat at intervals of 7 days for 4 or more courses.
Intravenous Breast cancer Adult: 10-60 mg/m2 often with cyclophosphamide and fluorouracil.
Intravenous Advanced lymphosarcoma Adult: Up to 30 mg/kg, followed by folinic acid rescue.
Intramuscular Acute lymphoblastic leukaemia Adult: Maintenance: 15 mg/m2 once or twice wkly, with other agents.
Intravenous Acute lymphoblastic leukaemia Adult: Maintenance: 2.5 mg/kg every 14 days.
Intramuscular Mycosis fungoides Adult: 50 mg wkly as a single dose or 2 divided doses.
Parenteral Psoriasis Adult: 10-25 mg wkly as a single dose. Adjust subsequent doses based on response. May be given via IV/IM admin.
Intramuscular Crohn's disease Adult: 25 mg once wkly for 16 wk. Maintenance: 15 mg wkly.
Special Populations: Monitor blood counts, renal and hepatic functions before, during and after each course. Reconstitution: Reconstitute to 2.5-5 mg/ml with normal saline, D5W, lactated Ringer's, or Elliott's B solution. Use preservative-free preparations. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Contraindications |
Severe renal or hepatic impairment, pre-existing profound bone marrow suppression in patients with psoriasis or rheumatoid arthritis, alcoholic liver disease, AIDS, pre-existing blood dyscrasias, pregnancy (in patients with psoriasis or rheumatoid arthritis), breast-feeding. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Warnings / Precautions |
Hepatic or renal impairment, bone marrow depression, elderly, neonates. Ulcerative disorders of the GI tract. Monitor haematological, renal and hepatic function, and GI toxicity regularly. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Adverse Reactions |
Ulceration of the mouth and GI disturbances (e.g. stomatitis and diarrhoea), bone marrow depression, hepatotoxicity, renal failure, skin reactions, alopecia, ocular irritation, arachnoiditis in intrathecal use, megaloblastic anaemia, osteoporosis, precipitation of diabetes, arthralgias, necrosis of soft tissue and bone, anaphylaxis, impaired fertility. Potentially Fatal: Pulmonary reactions (e.g. interstitial lung disease); neurotoxicity (e.g. leukoencephalopathy, paresis, demyelination) with intrathecal use; foetal deaths. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Overdose Reactions |
Nausea, vomiting, alopecia, melena, and renal failure. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Drug Interactions |
Decreased effectiveness with folic acid and its derivatives. Potentially Fatal: Increased toxicity with NSAIDs and salicylates; probenecid; some penicillins; aminoglycosides neomycin and paromomycin; sulfonamides such as sulfafurazole and sulfamethoxazole; co-trimoxazole or trimethoprim; nephrotoxic agents (e.g. cisplatin); ciclosporin; etretinate. Synergistic enhancement of effects with fluorouracil. Increased bioavailability of mercaptopurine. Reduces serum-valproate concentrations. Reduced serum concentrations with colestyramine. Increased serum concentrations with omeprazole. See Below for More methotrexate Drug Interactions |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Food Interactions |
May be given with meals to minimise GI discomfort. Serum levels may be decreased if taken with food. Decreased absorption in milk-rich food, decreased drug response with folate. Avoid ethanol (may be associated with increased liver injury). Avoid echinacea (has immunostimulant properties). | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Mechanism of Actions |
Methotrexate is a folic acid antagonist that inhibits DNA synthesis. It irreversibly binds to dihydrofolate reductase, inhibiting the formation of reduced folates, and thymidylate synthetase, resulting in inhibition of purine and thymidylic acid synthesis. Absorption: Rapidly absorbed from the GI tract at low doses, higher doses are less well absorbed. Rapidly and completely absorbed after IM doses. Peak plasma concentrations after 1-2 hr (oral), 30-60 min (IM). Distribution: Tissues and extracellular fluids; crosses the blood-brain barrier and placenta; enters breast milk. Small amounts in saliva and breastmilk. 50% bound to plasma proteins. Bound as polyglutamate conjugates, bound drug may remain in the body for several mth, particularly in the liver . Metabolism: Partly by intestinal flora. Does not undergo significant metabolism at low dose therapy; 7-hydroxy metabolite is detected at high-doses. Excretion: Primarily via urine; small amounts in bile, faeces. Some evidence of enterohepatic recirculation. Interindividual variation exists, patients with delayed clearance are at an increased risk of toxicity. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Administration |
Should be taken on an empty stomach. (Best taken on an empty stomach. May be taken w/ meals to reduce GI discomfort. Avoid taking w/ milk-rich products.) |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Storage Conditions |
Intramuscular: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. Intrathecal: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. Dilutions are stable for 7 days at room temperature, but are recommended to be used within 4-8 hr. Intravenous: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. Oral: Store tablets at room temperature (15-25°C). Protect from light. Parenteral: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
ATC Classification |
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 immunosuppressive agents. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Storage |
Intramuscular: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. Intrathecal: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. Dilutions are stable for 7 days at room temperature, but are recommended to be used within 4-8 hr. Intravenous: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. Oral: Store tablets at room temperature (15-25°C). Protect from light. Parenteral: Store intact vials at room temperature (15-25°C). Protect from light. Solutions diluted in D5W or normal saline are stable at room temperature (21-25°C) for 24 hr. Reconstituted solutions with a preservative may be stored under refrigeration for up to 3 mth, and up to 4 wk at room temperature. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Available As |
|
Methotrexate
Post Review about Methotrexate Click here to cancel reply.
Methotrexate Containing Brands
Methotrexate is used in following diseases
Drug - Drug Interactions of Methotrexate
Latest News
- FDA approves Ruconest for treatment of hereditary angioedema
- FDA recommend against aspirin to prevent First Heart Attacks
- FDA approves Pomalyst (pomalidomide) for advanced multiple myeloma
- FDA approves three new drug treatments for type 2 diabetes
- Long-term consequences of vaginal delivery on the pelvic floor
No comments yet.