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What are the possible side effects of Methotrexate Injection?

What are the possible side effects of Methotrexate Injection?

Methotrexate Injection can cause serious side effects, including:
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See “What is the most important information I should know about Methotrexate Injection?”
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Tumor lysis syndrome (TLS). TLS is caused by the fast breakdown of cancer cells. TLS can cause kidney failure and the need for dialysis treatment, abnormal heart rhythm, seizure, and sometimes death. Your healthcare provider may do blood tests to check you for TLS if you are receiving Methotrexate Injection as a cancer treatment. Your healthcare provider will treat you as needed to prevent or manage TLS if you develop it during treatment with Methotrexate Injection.
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New (secondary) cancers. New (secondary) cancers can happen in people who take or receive Methotrexate Injection at any dose.
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Certain blood cancers can happen during treatment with low-dose Methotrexate Injection. In some cases, these blood cancers may completely go away (regress completely) after Methotrexate Injection is stopped.
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If you develop one of these blood cancers during treatment with Methotrexate Injection, your healthcare provider will stop your treatment, and treat as needed if the new cancer does not go away after Methotrexate Injection is stopped.
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Increased risk of soft tissue and bone problems due to receiving Methotrexate Injection in combination with radiation therapy. In people who receive Methotrexate Injection, some soft tissue in your body may die and some bone cells may die. People who receive radiation therapy in combination with Methotrexate Injection have an increased risk of this happening.

The most common side effects of Methotrexate Injection include:

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mouth sores or ulcers
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nausea
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decreased white blood cell count. See “What is the most important information I should know about Methotrexate Injection?”
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upset stomach

Possible fertility problems (infertility) in males and females. Methotrexate Injection can cause fertility problems in males and females, and cause sperm production to stop in males, and menstrual problems in females. In females, your periods (menstrual cycle) may be irregular or completely stop when you receive Methotrexate Injection. Your periods may or may not return to normal following treatment. It is not known if your fertility will return after treatment. Talk to your healthcare provider about your risk for infertility if this is a concern for you.
These are not all of the possible side effects of Methotrexate Injection.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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