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Methotrexate

(meth oh trex' ate)

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IMPORTANT WARNING:   Return to top

Methotrexate may cause very serious side effects. Some side effects of methotrexate may cause death. You should only use methotrexate to treat life-threatening cancer, or certain other conditions that are very severe and that cannot be treated with other medications. Talk to your doctor about the risks of taking methotrexate for your condition.

Tell your doctor if you have or have ever had excess fluid in your stomach area or in the space around your lungs and if you have or have ever had kidney disease. Also tell your doctor if you are taking aspirin or other nonsteroidal anti-inflammatory medications (NSAIDs) such as ibuprofen (Advil, Motrin) or naproxen (Aleve, Naprosyn) or are being treated with radiation therapy. These conditions and treatments may increase the risk that you will develop serious side effects of methotrexate. Your doctor will monitor you more carefully and may need to change the doses of your medications.

Methotrexate may cause liver damage. Tell your doctor if you are taking any of the following medications: acitretin (Soriatane), azathioprine (Imuran), isotretinoin (Accutane), sulfasalazine (Azulfidine), or tretinoin (Vesanoid). Tell your doctor if you drink or have ever drunk large amounts of alcohol and if you have or have ever had liver disease, Your doctor may tell you that you should not take methotrexate unless you have a life-threatening cancer. Also tell your doctor if you have diabetes. Do not drink alcohol while you are taking methotrexate. Call your doctor immediately if you experience any of the following symptoms: nausea, extreme tiredness, lack of energy, loss of appetite, pain in the upper right part of the stomach, yellowing of the skin or eyes, or flu-like symptoms.

Methotrexate may cause lung damage. Tell your doctor if you have or have ever had lung disease. Call your doctor immediately if you experience any of the following symptoms: dry cough, fever, or shortness of breath.

Methotrexate may cause kidney damage. Be sure to drink plenty of fluids during your treatment with methotrexate, especially if you exercise or are physically active. Call your doctor if you think you might be dehydrated (do not have enough fluid in your body). You may become dehydrated if you sweat excessively or if you vomit, have diarrhea, or have a fever.

Methotrexate may cause a decrease in the number of blood cells made by your bone marrow. Tell your doctor if you have or have ever had a low blood count (decrease in the number of blood cells in your body), anemia (red blood cells do not bring enough oxygen to all parts of the body), or any other problem with your blood cells. Your doctor may tell you not to take methotrexate unless you have a life-threatening cancer. Call your doctor immediately if you experience any of the following symptoms: sore throat, chills, fever, or other signs of infection; unusual bruising or bleeding; excessive tiredness; weakness; pale skin; dizziness; confusion; fast heartbeat; shortness of breath; or difficulty falling asleep or staying asleep.

Methotrexate may cause damage to your intestines. Tell your doctor if you have or have ever had stomach ulcers or ulcerative colitis (condition in which part or all of the lining of the intestine is swollen or worn away). If you develop sores in your mouth or diarrhea, stop taking methotrexate and call your doctor immediately.

Methotrexate may cause a severe rash that may be life-threatening. If you develop a rash, blisters, or a fever, call your doctor immediately.

Methotrexate may decrease the activity of your immune system, and you may develop serious infections. Tell your doctor if you have any type of infection and if you have or have ever had any condition that affects your immune system such as human immunodeficiency syndrome (HIV) or acquired immunodeficiency syndrome (AIDS). Your doctor may tell you that you should not take methotrexate unless you have a life-threatening cancer. If you experience signs of infection such as a sore throat, cough, fever, or chills, call your doctor immediately.

Taking methotrexate may increase the risk that you will develop lymphoma (cancer that begins in the cells of the immune system). If you do develop lymphoma, it might go away without treatment when you stop taking methotrexate, or it might need to be treated with chemotherapy.

If you are taking methotrexate to treat cancer, you may develop certain complications as methotrexate works to destroy the cancer cells. Your doctor will monitor you carefully and treat these complications if they occur.

Keep all appointments with your doctor and the laboratory. Your doctor will order lab tests before, during, and after your treatment to check your body's response to methotrexate and to treat side effects before they become severe.

Women who are taking methotrexate, or whose male partners are taking methotrexate are less likely to become pregnant than women who are not taking methotrexate or whose partners are not taking the medication. However, you should not assume that you or your partner cannot become pregnant while you are taking methotrexate. Tell your doctor if you or your partner is pregnant or plan to become pregnant. If you are female, you will need to take a pregnancy test before you begin taking methotrexate. Use a reliable method of birth control so that you or your partner will not become pregnant during or shortly after your treatment. If you are male, you and your female partner should continue to use birth control for 3 months after you stop taking methotrexate. If you are female, you should continue to use birth control until you have had one menstrual period that began after you stopped taking methotrexate. If you or your partner become pregnant, call your doctor immediately. Methotrexate may harm the fetus.

About your treatment   Return to top

Your doctor has ordered methotrexate to help treat your illness. Methotrexate comes as a tablet to take by mouth. Your doctor will tell you how often you should take methotrexate. The schedule depends on the condition you have and on how your body responds to the medication.

You may take methotrexate on a rotating schedule that alternates several days when you take methotrexate with several days or weeks when you do not take the medication. Follow these directions carefully and ask your doctor or pharmacist if you do not know when to take your medication.

Follow the directions on your prescription label carefully and ask your doctor or pharmacist to explain anything you do not understand. Take methotrexate exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Do not stop taking methotrexate without talking to your doctor.

This medication is used to treat:

Methotrexate is in a class of medications known as antimetabolites. Methotrexate treats cancer by slowing the growth of cancer cells. Methotrexate treats psoriasis by slowing the growth of skin cells. Methotrexate may treat rheumatoid arthritis by slowing the activity of the immune system.

If you are taking methotrexate to treat rheumatoid arthritis, it may take 3 to 6 weeks or longer for you to feel the full benefit of methotrexate. Continue to take methotrexate even if you feel well. Do not stop taking methotrexate without talking to your doctor.

If you are taking methotrexate once a week to treat rheumatoid arthritis and you forget a dose of your medication, take the missed dose as soon as you remember it. However, if more than 24 hours have passed, skip the missed dose and continue your regular dosing schedule. If you are taking methotrexate more often than once a week, ask your doctor what you should do if you miss a dose. Do not take a double dose to make up for a missed one.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine   Return to top

Methotrexate is also sometimes used to treat Crohn's disease (a condition in which the immune system attacks the lining of the digestive tract, causing pain, diarrhea, weight loss, and fever). Talk to your doctor about the risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Precautions   Return to top

Before taking methotrexate,

Side effects   Return to top

Methotrexate may cause side effects. Tell your doctor if any of the following symptoms are severe or do not go away:

Some side effects can be serious. If you experience any of the following symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:

Methotrexate may cause other side effects. Tell your doctor if you have any unusual problems while you are taking this medication.

Storage conditions   Return to top

Keep methotrexate in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose   Return to top

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

It is important to get medical help right away when you realize that you have taken too much methotrexate. If you take an overdose of methotrexate, there is a medication that you can take to stop the overdose from causing serious harm. This medication works best when it is taken as soon as possible after the overdose.

Symptoms of overdose may include:

Special instructions   Return to top

Do not let anyone else take your medication. Ask your pharmacist if you have any questions about refilling your prescription.

Brand names   Return to top

  • Rheumatrex®
  • Trexall®

Other names   Return to top

  • Amethopterin
  • MTX

Last Revised - 10/01/2006
Last Reviewed - 08/01/2007


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