Methotrexate (Injection)


Methotrexate (meth-oh-TREX-ate)

Treats cancer of the blood, bone, lung, breast, head, or neck. Also treats rheumatoid arthritis and psoriasis.

Brand Name(s)

There may be other brand names for this medicine.

When This Medicine Should Not Be Used

You should not receive this medicine if you have had an allergic reaction to methotrexate, or if you are breastfeeding. You should not use this medicine for arthritis or psoriasis if you are pregnant, if you have liver disease, if you have blood problems (such as anemia), or if you have a weak immune system.

How to Use This Medicine


  • Medicines used to treat cancer are very strong and can have many side effects. Before receiving this medicine, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.
  • Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot under your skin, into a muscle, into an artery, or into your spine (back or neck).
  • You will receive this medicine while you are in a hospital or cancer treatment center. A nurse or other trained health professional will give you this medicine.
  • You may be taught how to give your medicine at home. Make sure you understand all instructions before giving yourself an injection. Do not use more medicine or use it more often than your doctor tells you to.
  • Use a new needle and syringe each time you inject your medicine.
  • Your doctor will give you a few doses of this medicine until your condition improves, and then may switch you to an oral medicine that works the same way. Talk to your doctor if you have any concerns.

If a dose is missed:

  • This medicine needs to be given on a fixed schedule. If you miss a dose, call your doctor, home health caregiver, or treatment clinic for instructions.

How to Store and Dispose of This Medicine

  • If you store this medicine at home, keep it at room temperature, away from heat, moisture, and direct light. This medicine may come as a powder or a liquid that must be mixed with another liquid before you use it. Do not mix the medicine and the liquid together until just before you use the medicine. Ask your doctor or home health caregiver if you have questions.
  • Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets. Follow any special instructions about how to throw away empty medicine bottles, tubes, or bags.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are also using aspirin, azathioprine (Imuran®), mercaptopurine (Purinethol®), phenylbutazone, phenytoin (Dilantin®), probenecid (Benemid®), or theophylline (Theo-Dur®). Tell your doctor if you are also using antibiotics (such as amoxicillin, chloramphenicol, penicillin, tetracycline, Amoxil®, Augmentin®, Chloromycetin®, or Sumycin®), sulfa drugs (such as sulfamethoxazole, sulfasalazine, sulfisoxazole, Azulfidine®, Bactrim®, Gantrisin®, or Septra®), stomach medicine (such as esomeprazole, lansoprazole, omeprazole, pantoprazole, Nexium®, Prevacid®, Prilosec®, or Protonix®), and vitamin supplements that contain folic acid.
  • Make sure your doctor knows if you are also using pain or arthritis medicine (such as aspirin, diclofenac, ibuprofen, indomethacin, naproxen, Advil®, Aleve®, Bextra®, Celebrex®, Motrin®, or Vioxx®) or steroid medicines (such as prednisone). Tell your doctor if you are also receiving cancer treatments (such as cisplatin, Platinol®) or radiation treatments.
  • Tell your doctor if you have used methotrexate before for any reason.
  • Make sure your doctor knows if you drink alcohol.
  • Talk to your doctor before getting flu shots or other vaccines while you are receiving this medicine. Vaccines may not work as well, or they could make you ill while you are using this medicine.

Warnings While Using This Medicine

  • Using this medicine while you are pregnant can harm your unborn baby. The medicine may also cause birth defects if the father is using it when his sexual partner becomes pregnant. Men should continue birth control for at least 3 months after stopping treatment. Women should continue birth control for 2 menstrual periods after stopping treatment. Tell your doctor right away if pregnancy occurs while you are using this medicine.
  • Make sure your doctor knows if you have kidney disease, liver disease (including cirrhosis or hepatitis), anemia, bone marrow problems, brain disease, diabetes, lung problems, stomach ulcers, a weak immune system (such as HIV or AIDS), or any infection.
  • Stop using this medicine and check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, unusual tiredness or weakness, or yellow eyes or skin. These could be symptoms of a serious liver problem.
  • If you have severe diarrhea, ask your doctor before taking any medicine to stop the diarrhea.
  • This medicine lowers the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
  • This medicine may increase your risk for lymphoma (cancer of the lymph system). In most patients, this lymphoma does not need to be treated and goes away after you stop using methotrexate.
  • This medicine may cause a serious reaction called tumor lysis syndrome. Tell your doctor right away if you have a decrease or change in the amount you urinate; joint pain, stiffness, or swelling; lower back, side, or stomach pain; rapid weight gain; swelling of the feet or lower legs; or unusual tiredness or weakness.
  • Serious skin reactions can occur with this medicine. Check with your doctor right away if you have any of the following symptoms: blistering, peeling, or loosening of the skin; chills; diarrhea; itching; joint or muscle pain; rash; red skin lesions, often with a purple center; sores, ulcers, or white spots in the mouth or on the lips; or unusual tiredness or weakness.
  • This medicine may make you dizzy or tired. Do not drive, use machines, or do anything else that could be dangerous until you know how this medicine affects you.
  • This medicine may make your skin more sensitive to sunlight. Use a sunscreen when you are outdoors. Avoid sunlamps and tanning beds.
  • Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.
  • Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments. Blood tests, urine tests, and chest x-rays may be needed periodically.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, or red skin rash
  • Change in how much or how often you urinate
  • Chest pain, shortness of breath, trouble breathing, or blue lips or fingers
  • Dark-colored urine or pale stools
  • Fever, chills, dry cough, sore throat, and body aches
  • Nausea, vomiting, diarrhea, loss of appetite, or stomach pain
  • Seizures, confusion, numbness, trouble seeing, or headache
  • Sores or white patches on your lips, mouth, or throat
  • Unusual bleeding, bruising, or weakness
  • Yellowing of the skin or the whites of your eyes

If you notice these less serious side effects, talk with your doctor:

  • Hair loss

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last Reviewed on 06/12/2013

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission ( URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2013 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

This page was last updated: September 18, 2013

Average rating (0)