Methotrexate
Trade Names:
Amethopterin, Folex, Mexate, MTX
Type of Drug:
Methotrexate belongs to a general group of chemotherapy drugs known as antimetabolites. It is used to treat choriocarcinoma, leukemia in the spinal fluid, osteogenic sarcoma, breast cancer, and head and neck cancers.
How Drug Works:
Methotrexate prevents cells from making DNA and RNA by interfering with the synthesis of nucleic acids, thus stopping the growth of cancer cells.
How Drug Is Given:
Methotrexate is given as a pill by mouth, as an injection in a vein for up to 20 minutes, or as an injection into a muscle. The pills are usually taken as a single dose at bedtime. If the pills cause stomach upset, take an antacid or antinausea pill 1 hour before taking the methotrexate. Methotrexate can also be injected into the spinal cord to kill any cancer cells there. If methotrexate is given in medium or high doses, leucovorin calcium is given 24 hours later, then every 6 hours for up to 8 doses to ÒrescueÓ normal cells. The dose depends on your size, the type of cancer being treated, and how well your kidneys are working. Keep the medicine in a tightly closed container away from heat and moisture and out of the reach of children and pets.
How Should I Take This Drug?
Take this drug exactly as directed by your doctor. If you do not understand the instructions, ask your doctor or nurse to explain them to you. This drug can be given at different strengths depending on the type of cancer being treated. Dosage may vary depending on your weight and your type of cancer.
Read the following information. If you do not understand it or if any of it causes you special concern, check with your doctor.

Before taking this drug, tell your doctor:

  • If you are trying to become pregnant, are pregnant, or breastfeeding. This drug may cause birth defects if either the male or female is taking it at the time of conception or during pregnancy. Men and women who are taking this drug need to use some kind of birth control. However, do not use oral contraceptives ("the pill") without checking with your doctor.

  • If you think you may want to have children in the future. Many chemotherapy drugs can cause sterility.

  • If you have any of the following medical problems: chickenpox or exposure to chickenpox, gout, heart disease, congestive heart failure, shingles, kidney stones, liver disease, or other forms of cancer.

  • If you are taking any other prescription or over-the-counter drugs, including vitamins and herbals.
Should I avoid any other medicines, foods, alcohol, and/or activities?
Your prescription and nonprescription medicines may interact with other drugs, causing harm. Certain foods or alcohol can also interact with drug products. Never begin taking a new medicine"prescription or nonprescription"without asking your doctor or nurse if it will interact with alcohol, food, or other medicines. Some drug products can cause drowsiness and affect activities such as driving.
Precautions:
While you are being treated with methotrexate, and after you stop treatment, do not have any immunizations (vaccinations) without your doctor's okay. Try to avoid contact with people who have recently taken the oral polio vaccine. Check with your doctor about this.
It is important not to drink alcohol when receiving methotrexate. Otherwise, risk of liver damage is increased. Also, if you are taking folic acid, vitamin preparations that contain folic acid, or nonsteroidal anti-inflammatory drugs, make sure to tell your doctor before starting this drug.
Methotrexate can lower your blood counts (white blood cells, red blood cells, platelets). Your doctor will check your blood counts before and after each treatment to see its effect. Your doctor or nurse will give you specific instructions if your blood counts are low.
Methotrexate can decrease your white blood cell count, especially 7 to 9 days after the drug is given. This can increase your risk of getting an infection. Report fever of 100.5¡F or higher, or signs of infection such as pain in passing your urine, or coughing, and bringing up sputum.
Methotrexate can decrease your platelet count. This can increase your risk of bleeding. DO NOT take any aspirin or aspirin-containing medicines. Report unusual bruising, or bleeding such as nosebleeds, bleeding gums when you brush your teeth, or black, tarry stools.
While receiving high-dose methotrexate, you will receive extra intravenous fluid with a medicine called sodium bicarbonate to flush the medicine through your kidneys. After the treatment, it is important to drink extra liquids and take the bicarbonate tablets as directed by your nurse or doctor.
Methotrexate can cause you to be very sensitive to sunlight or bright ultraviolet light. You can get a very bad sunburn. Wear sunglasses and protective clothing when out in strong sunlight. Always wear sunscreen when out in the sun.
Methotrexate is an effective drug for many cancers, and is given at doses that are low, medium, and high. At medium and high doses, severe side effects are prevented by giving it with leucovorin. Leucovorin MUST be taken exactly as directed. Leucovorin is also given when methotrexate is injected into the spinal canal to kill cancer cells in the spinal fluid.
Tell all the doctors, dentists, and pharmacists you visit that you are taking this drug.
  • Most of the following side effects probably will not occur.
  • Your doctor or nurse will want to discuss specific care instructions with you.
  • They can help you understand these side effects and help you deal with them.
Side Effects:
More Common Side Effects
  • Nausea (high dose)
  • Vomiting (high dose)
  • Sores in mouth or on lips
  • Diarrhea
  • Increased risk of sunburn
  • Skin changes in areas previously treated with radiation
  • Loss of appetite
Less Common Side Effects
  • Decreased white blood cell count with increased risk of infection
  • Decreased platelet count with increased risk of bleeding
  • Kidney damage (high dose)
Rare Side Effects
  • Nausea (low and medium dose)
  • Vomiting (low and medium dose)
  • Liver toxicity
  • Lung collapse (high dose)
  • Allergic inflammation of the lung (high dose) with fever, cough, and shortness of breath
  • Hair loss
  • Rash, itching
  • Dizziness
  • Blurred vision
Other side effects not listed above can also occur in some patients. Tell your doctor or nurse if you develop any problems.
FDA Approval: This drug is approved for cancer treatment.