Pfizer Methotrexate Injection 5 g

Adult dosage

1. Leukemia Administer 5～10 mg of methotrexate orally per day for 3～6 days per week. The dose may be increased or decreased according to the patient's tolerability and the severity of symptoms. 2. Trophoblastic disease Administer 10～30 mg of this medicine orally per day (adjust as appropriate). Use a 5-day treatment cycle, and repeat after a drug-free period of 7～12 days. 3. Rheumatoid arthritis It is recommended to administer a test dose of 5～10 mg of this medicine orally once, 1 week before treatment, to test for idiosyncratic adverse reactions. Administer 7.5～20 mg orally once weekly, or administer 2.5 mg orally 3 times at 12-hour intervals. The schedule may be gradually increased to achieve an optimal response, but the total weekly dose should not exceed 20 mg. Once a response is achieved, reduce the schedule to the lowest possible dose. 4. Psoriasis It is recommended to administer a test dose of 5～10 mg of this medicine orally once, 1 week before treatment, to test for idiosyncratic adverse reactions. For severe, refractory psoriasis that has not responded to other medicines, administer 7.5～20 mg orally once weekly or orally in 3 divided doses at 12-hour intervals. Administration of the injectable formulation for psoriasis It is recommended to administer a test dose of 5～10 mg orally once, 1 week before treatment, to test for idiosyncratic adverse reactions. For severe, uncontrolled psoriasis refractory to existing therapy, 10～25 mg is generally administered orally once weekly, but may also be administered intravenously or intramuscularly. For administration by injection, adjust the dose according to the patient's response. Other indications for the injectable formulation Breast cancer: Administer 10～60 mg/㎡ intravenously. Lung cancer: Administer 20～100 mg/㎡ by intravenous infusion or injection. Head and neck cancer: Administer 240～1,080 mg/㎡ by intravenous infusion, followed by leucovorin calcium rescue therapy. Bladder cancer: Administer up to 100 mg intravenously by injection or infusion every 1 or 2 weeks. Osteosarcoma: Administer 600～9,000 mg/㎡ by intravenous infusion, followed by leucovorin calcium rescue therapy. Non-Hodgkin lymphoma: Administer 90～900 mg/㎡ by intravenous injection or infusion, followed by high-dose leucovorin calcium. The above dosing regimens may be used alone or in combination with other medicines. When used in combination, the dose should be reduced, taking into account the increased toxicity.

Children's dosage

1. Leukemia Administer 1.25～2.5 mg to infants and 2.5～5 mg to children orally for 3～6 days per week. Injectable formulation Meningeal leukemia in children: Administer 12～15 mg/㎡ (approximately 0.4～0.5 mg per kg of body weight) by intrathecal injection at 1-week intervals until the cerebrospinal fluid returns to normal. Trophoblastic disease: Use a 5-day treatment cycle and administer 10～30 mg/㎡ per day (adjust as appropriate) by intramuscular injection for 5 days. Allow a drug-free period of 7～12 days or until adverse reactions subside. The cycle may be repeated 3～5 times.

This medication should only be taken once a week when treating rheumatoid arthritis or psoriasis, and serious side effects can occur if the dosing regimen is not strictly followed. The treatment using this drug alternately with fluorouracil is risky and must be carried out under the supervision of a physician, and should only be used in medical institutions that can respond to emergencies. Caution should be taken when used in high doses with proton pump inhibitors, as it may increase blood concentrations of this drug and result in toxicity. Patients with allergies to this drug or severely impaired renal or liver function, patients with pleural effusion or ascites, patients with certain blood disorders or immunodeficiencies, pregnant women or women who may become pregnant, and nursing mothers should not use this medication. Patients with diarrhea, stomatitis, gastric ulcers, blood disorders, infections, children, elderly patients, etc. should use this medication with caution and should consult a doctor immediately if any abnormal symptoms appear. This medication may cause serious allergic reactions, gastrointestinal bleeding, pneumonia, hepatitis, renal damage, skin abnormalities, infections, and blood cell reductions, so the patient's condition should be closely monitored while taking it. Long-term use requires regular monitoring of bone marrow function, liver, and kidney functions, and if any abnormalities are found, the medication should be discontinued or the dosage adjusted. Additionally, this medication can affect reproductive function, and pregnancy should be avoided during and for some time after treatment, and men should also be advised to use contraception during and for some time after treatment. This drug may interact with several medications, so when taking other medications together, a doctor or pharmacist should be consulted, especially caution is needed in combination with specific antibiotics, anti-inflammatory drugs, diuretics, and vitamin preparations. Pregnant or nursing women should not take this medication, and if unavoidable, should discontinue breastfeeding. Special caution is needed as the safety of this medication in children and the elderly has not been sufficiently confirmed. In case of overdose, immediate medical attention should be sought, and specific antidotes may be used to reduce toxicity. This medication should not be mixed with other drugs and should only be diluted with the designated diluent, and any remaining solution after use should be discarded. Store this medication out of the reach of children and do not transfer it to other containers.

• Shock
• anaphylactic symptoms
• hemorrhagic enteritis
• necrotizing enteritis
• abdominal pain
• diarrhea
• nausea
• vomiting
• stomatitis
• loss of appetite

This medication should be stored in a sealed container to prevent air and moisture from entering. It is also advisable to keep it away from direct sunlight and store it in a cool place, below 25 degrees Celsius.

Appearance

A clear solution injection containing a yellow to orange clear liquid in a transparent vial.

Package unit

5 g/50mL X 1 vial