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URL of this page: https://medlineplus.gov/druginfo/meds/a682018.html

Methotrexate Injection

pronounced as (meth'' oh trex' ate)

IMPORTANT WARNING:

Methotrexate may cause very serious, life-threatening side effects. Talk to your doctor about the risks of receiving methotrexate injection for your condition.

Methotrexate injection may cause a serious, life-threatening reaction that may occur while or shortly after you receive this medication. If you experience any of the following symptoms during or after receiving methotrexate, tell your doctor immediately: rash, itching, hives, throat tightness, swelling of the face, lips, tongue, or throat, or trouble swallowing; runny or stuffy nose, dizziness or lightheadedness, difficulty breathing, chest pain, wheezing, or feeling faint.

Tell your doctor if you or your partner is pregnant or plan to become pregnant. Methotrexate injection may harm your unborn baby. If you are female, you will need to take a pregnancy test before you receive methotrexate and use a reliable method of birth control during your treatment and for 6 months after your final dose. If you are male, you and your female partner should use a reliable method of birth control during your treatment and for 3 months after your last dose. If you or your partner become pregnant, call your doctor immediately. Methotrexate may cause harm or death to the fetus.

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 or are receiving dialysis treatments. Also tell your doctor if you are taking nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, choline magnesium trisalicylate (Tricosal, Trilisate), ibuprofen (Advil, Motrin), magnesium salicylate (Doan's), naproxen (Aleve, Naprosyn), or salsalate. These conditions and medications may increase the risk that you will develop serious side effects of methotrexate. Your doctor will monitor you more carefully and may need to give you a lower dose of methotrexate or stop your treatment with methotrexate.

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 number of any type of blood cells or any other problem with your blood cells. Call your doctor immediately if you experience any of the following symptoms: sore throat, chills, fever, ongoing cough and congestion, or other signs of infection; unusual bruising or bleeding; unusual tiredness or weakness; pale skin; or shortness of breath.

Methotrexate may cause liver damage, especially when received for a long period of time. Tell your doctor if you drink or have ever drunk large amounts of alcohol or if you have or have ever had liver disease. Your doctor may not want you to receive methotrexate injection unless you have a life-threatening form of cancer because there is a higher risk that you will develop liver damage. The risk that you will develop liver damage may also be higher if you are elderly, obese, or have diabetes. Ask your doctor about the safe use of alcoholic beverages while you are receiving methotrexate injection. Tell your doctor if you are taking any of the following medications: acitretin (Soriatane), azathioprine (Imuran), isotretinoin (Accutane), sulfasalazine (Azulfidine), or tretinoin (Vesanoid). 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 damage to the lining of your mouth, stomach or intestines. Tell your doctor if you have or have ever had stomach ulcers or ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum). Call your doctor immediately if you experience any of the following symptoms: mouth sores, diarrhea, black, tarry, or bloody stools, and vomiting, particularly if vomit is bloody or looks like coffee grounds.

Using 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 receiving methotrexate, or it might need to be treated with chemotherapy.

Methotrexate may cause serious or life-threatening skin reactions. If you experience any of the following symptoms, call your doctor immediately: fever, rash, blisters, or peeling skin.

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. Your doctor may tell you that you should not receive methotrexate unless you have life-threatening cancer. If you experience signs of infection such as a sore throat, cough, fever, or chills, call your doctor immediately.

If you receive methotrexate while you are being treated with radiation therapy for cancer, methotrexate may increase the risk that the radiation therapy will cause damage to your skin, bones, or other parts of your body.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain 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.

Why is this medication prescribed?

Methotrexate injection is used alone or in combination with other medications:

  • to treat certain types of acute lymphocytic leukemia (ALL) in adults and children;
  • to treat or prevent meningeal leukemia (cancer in the covering of the spinal cord and brain) in adults and children;
  • to treat certain types of non-Hodgkin's lymphoma (types of cancer that begin in a type of white blood cells that normally fights infection) in adults and children;
  • to treat osteosarcoma (cancer that forms in bones) after surgery to remove the tumor in adults and children;
  • to treat cutaneous T-cell lymphoma (CTCL, a group of cancers of the immune system that first appear as skin rashes);
  • to treat breast cancer in adults;
  • to treat certain cancers of the head and neck in adults;
  • to treat gestational trophoblastic tumors (a type of tumor that forms inside a woman's uterus when pregnant) in adults;
  • to treat rheumatoid arthritis (RA; a condition in which the body attacks its own joints, causing pain, swelling, and loss of function) in adults;
  • to treat polyarticular juvenile idiopathic arthritis (pJIA; a type of childhood arthritis that affects five or more joints during the first six months of the condition, causing pain, swelling, and loss of function) in children; and
  • to treat severe psoriasis (a skin disease in which red, scaly patches form on some areas of the body) in adults.

Methotrexate is in a class of medications called antimetabolites. Methotrexate treats cancer by slowing the growth of cancer cells. Methotrexate treats psoriasis by slowing the growth of skin cells to stop scales from forming. Methotrexate may treat rheumatoid arthritis and polyarticular juvenile idiopathic arthritis by decreasing the activity of the immune system.

How should this medicine be used?

Methotrexate injection comes as a powder to be mixed with liquid to be injected intramuscularly (into a muscle), intravenously (into a vein), subcutaneously (just under the skin), or intrathecally (into the fluid-filled space of the spinal canal). The length of treatment depends on the types of drugs you are taking, how well your body responds to them, and the type of cancer or condition you have.

Your doctor may give you medication(s) to prevent or treat side effects from methotrexate injection.

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

Other uses for this medicine

Methotrexate is also sometimes used in combination with other medications to treat bladder cancer. It is also sometimes used to treat Crohn's disease (condition in which the immune system attacks the lining of the digestive tract, causing pain, diarrhea, weight loss and fever) and other autoimmune diseases (conditions that develop when the immune system attacks healthy cells in the body by mistake). Ask 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.

What special precautions should I follow?

Before receiving methotrexate injection,

  • tell your doctor and pharmacist if you are allergic to methotrexate, any other medications, benzyl alcohol, or any of the ingredients in methotrexate injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention the medications listed in the IMPORTANT WARNING section and any of the following: certain antibiotics such as chloramphenicol (Chloramycetin), penicillins, and tetracylcines; folic acid (available alone or as an ingredient in some multivitamins); other medications for rheumatoid arthritis; phenytoin (Dilantin); probenecid (Benemid); proton pump inhibitors (PPIs) such as esomeprazole (Nexium), omeprazole (Prilosec, Prilosec OTC, Zegerid), pantoprazole (Protonix); sulfonamides such as co-trimoxazole (Bactrim, Septra), sulfadiazine, sulfamethizole (Urobiotic), and sulfisoxazole (Gantrisin); and theophylline (Theochron, Theolair). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had any of the conditions mentioned in the IMPORTANT WARNING section, seizures, or a low level of folate in your blood.
  • do not breastfeed while you are receiving methotrexate injection and for at least 1 week after your final dose.
  • you should know that this medication may decrease fertility in women and men. Talk to your doctor about the risks of taking this medication if you have concerns about fertility.
  • you should know that methotrexate may cause dizziness or make you feel drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving methotrexate injection.
  • plan to avoid unnecessary or prolonged exposure to sunlight or ultraviolet light (tanning beds and sunlamps) and to wear protective clothing, sunglasses, and sunscreen. Methotrexate may make your skin sensitive to sunlight or ultraviolet light. If you have psoriasis, your sores may get worse if you expose your skin to sunlight while you are receiving methotrexate.
  • do not have any vaccinations during your treatment with methotrexate without talking to your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Call your doctor right away if you cannot keep an appointment to receive methotrexate injection.

What side effects can this medication cause?

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

  • joint or muscle pain
  • reddened eyes
  • swollen gums
  • hair loss

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

  • vomiting
  • blurred vision or sudden loss of vision
  • sudden fever, severe headache, and stiff neck
  • seizures
  • confusion or memory loss
  • weakness or difficulty moving one or both sides of the body
  • difficulty walking or unsteady walking
  • loss of consciousness
  • impaired speech
  • decreased urination
  • swelling of the face, arms, hands, feet, ankles, or lower legs

Some people who received methotrexate injection developed other forms of cancer. Talk to your doctor about the risks of receiving this medication.

Methotrexate may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • sores in the mouth and throat
  • sore throat, chills, fever, ongoing cough and congestion, or other signs of infection
  • unusual bruising or bleeding
  • black and tarry or bloody stools
  • bloody vomit
  • vomited material that looks like coffee grounds

What other information should I know?

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Abitrexate®
  • Folex®
  • Mexate®
  • Otrexup®
  • Rasuvo®
  • Reditrex®

Other names

  • Amethopterin
  • MTX

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 07/15/2021