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Generic Name Brand Name
methotrexate Trexall

How It Works

Methotrexate is similar to the vitamin called folic acid. It works by competing with folic acid in cells. This blocks the way the cell is able to make genetic material, and the cell dies.

Methotrexate may be given as a pill or as a shot in the vein (intravenously, or IV) or in the muscle (intramuscularly, or IM).

Why It Is Used

Methotrexate can be used to treat several conditions and diseases, including:

How Well It Works

Methotrexate effectively treats many conditions and diseases, including:

  • Cancer. The type and extent of a cancer will determine whether methotrexate is used. It is commonly used in combination with other chemotherapy medicines.
  • Autoimmune diseases. Methotrexate is used to relieve joint pain and other symptoms. It is given to help control diseases such as rheumatoid arthritis, juvenile idiopathic arthritis, psoriasis, and Sjögren's syndrome.
  • Ectopic pregnancy. Methotrexate is used to end an ectopic pregnancy in early pregnancy. It is not used to treat a ruptured ectopic pregnancy.

Side Effects

Side effects from methotrexate are usually temporary and occur more often with long-term use. Side effects may include:

Less common side effects include:

  • Sun sensitivity and easy sunburning.
  • Diarrhea or blood in the stool.
  • Mouth sores.
  • Easy bruising and bleeding.
  • Skin rash or sores.
  • Headaches.
  • Chills and fever.
  • Lightheadedness.

Long-term side effects may include:

  • Liver damage. The risk of liver damage is increased in people who have other problems, such as diabetes, liver disease, or a history of alcohol abuse.
  • Lung problems.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Methotrexate can cause birth defects. Do not use this drug if you are pregnant or wish to become pregnant or father a child while you are taking it.

Many antibiotics can increase the level of methotrexate in your blood. Make sure your doctor knows that you are taking methotrexate if you need to take an antibiotic for another problem.

You will have your blood drawn often while you are taking methotrexate.

Do not drink alcoholic beverages, including beer and wine, while you are being treated with methotrexate.

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.

By Healthwise Staff
Primary Medical Reviewer Sarah Marshall, MD - Family Medicine
Specialist Medical Reviewer Douglas A. Stewart, MD - Medical Oncology
Current as of June 28, 2013

WebMD Medical Reference from Healthwise

Last Updated: June 28, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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