methotrexate - injection
GENERIC NAME: METHOTREXATE - INJECTION (meth-oh-TREX-ate)
WARNING: Methotrexate has infrequently caused serious (sometimes fatal) side effects. Therefore, this medication should be used only to treat cancer or severe diseases caused by an overactive immune system (such as psoriasis, rheumatoid arthritis).
Methotrexate formulations with preservatives must not be used for high-dose treatment or injected into the spine (intrathecal).
Methotrexate has caused birth defects and death in unborn babies. Women must avoid becoming pregnant while using this medication. Pregnant women who have psoriasis or rheumatoid arthritis must not use methotrexate. (See also Precautions section.)
Methotrexate (usually at high dosages) has rarely caused severe (sometimes fatal) blood/bone marrow problems (decreasing your body's ability to fight infections) and stomach/intestinal disease (such as bleeding) when used at the same time as non-steroidal anti-inflammatory drugs (NSAIDs such as indomethacin, ketoprofen). Therefore, NSAIDs should not be used with high-dose methotrexate. Caution is advised if you also take aspirin. NSAIDs/aspirin may be used with low-dose methotrexate such as for the treatment of rheumatoid arthritis if directed by your doctor. If your doctor has directed you to take low-dose aspirin for heart attack or stroke prevention (usually at dosages of 81-325 milligrams a day), you should continue taking it unless your doctor instructs you otherwise. Ask your doctor or pharmacist for more details on the safe use of these drugs (such as close monitoring by your doctor, keeping the same doses of NSAIDs).
In rare instances, this drug may also cause liver problems when it is used for long periods of time. If you are using methotrexate long term, a liver biopsy is usually recommended.
Methotrexate use has rarely caused serious (sometimes fatal) side effects, such as lung problems, lung infections (Pneumocystis jiroveci pneumonia), skin reactions, diarrhea, and mouth sores (ulcerative stomatitis). (See also Side Effects section.)
Lumps (tumors/abnormal growths) may very infrequently appear during methotrexate use. The drug must be stopped and treatment may be needed. Tell your doctor right away if new lumps/growths occur.
When used to treat tumors, methotrexate sometimes causes side effects due to the rapid destruction of cancer cells (tumor lysis syndrome). To lower your risk, drink plenty of fluids unless your doctor directs you otherwise. Also, your doctor may prescribe an additional medication. Tell your doctor right away if you have symptoms such as irregular heartbeat, low back/side pain, pink/bloody urine, change in amount of urine, painful urination, or muscle spasms/weakness.
When this medication is used with radiation treatment, it may rarely increase the risk of tissue and bone damage. Discuss the risks and benefits of your treatment with your doctor.
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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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