Methotrexate is usually taken once or twice per week and not every day. You must use the correct dose for your condition. Some people have died after taking methotrexate every day by accident.
Do not use methotrexate to treat psoriasis or rheumatoid arthritis if you have liver disease (especially if caused by alcoholism), or a blood cell or bone marrow disorder.
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Do not use methotrexate if you are pregnant or breast-feeding a baby.
Methotrexate can lower blood cells that help your body fight infections and help your blood to clot. You may get an infection or bleed more easily. Call your doctor if you have unusual bruising or bleeding, or signs of infection (fever, chills, body aches).