This drug is FDA-approved for treating certain cancers and rheumatoid arthritis, but is used “off-label” to treat ectopic pregnancies and to induce abortion. It works by stopping the growth of rapidly dividing cells. It is used up through 49 days of pregnancy and given orally or by injection. Three to seven days after methotrexate is taken, misoprostol (the second medication used in the RU-486 abortions) is used vaginally.
Side effects of methotrexate include mouth ulcers, low white blood cell count, nausea, abdominal distress, fatigue, chills, fever, dizziness, decreased resistance to infection and anemia. Severe, sometimes fatal, bone marrow suppression and intestinal toxicity have been reported. Liver toxicity and cancer may occur (usually after prolonged use.) Severe, occasionally fatal, skin reactions have been reported. 28