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Methotrexate (injection)

Generic Name: methotrexate (injection) (meth oh TREX ate)
Brand Name: EmGyn Kit, Methotrexate Sodium, Preservative Free, Otrexup, Rasuvo

Medically reviewed by Drugs.com on Aug 10, 2020 – Written by Cerner Multum

What is methotrexate injection?

Methotrexate is used to treat leukemia and certain types of cancer of the breast, skin, head and neck, or lung.

Methotrexate is also used to treat severe psoriasis and rheumatoid arthritis in adults, and to treat active polyarticular-course juvenile rheumatoid arthritis in children.

Methotrexate is often used when other medicines have not been effective.

Methotrexate may also be used for purposes not listed in this medication guide.

Important Information

Methotrexate should not be used during pregnancy to treat arthritis or psoriasis. Methotrexate is sometimes used to treat cancer during pregnancy. Tell your doctor if you are pregnant or plan to become pregnant.

Do not use methotrexate to treat psoriasis or rheumatoid arthritis if you have low blood cell counts, a weak immune system, alcoholism or chronic liver disease, or if you are pregnant or breastfeeding.

Methotrexate can cause serious or fatal side effects. Tell your doctor if you have diarrhea, mouth sores, cough, shortness of breath, upper stomach pain, dark urine, numbness or tingling, muscle weakness, confusion, seizure, or skin rash that spreads and causes blistering and peeling.

Before taking this medicine

You should not use methotrexate if you are allergic to it. Methotrexate should not be used to treat psoriasis or rheumatoid arthritis if you have:

  • alcoholism, cirrhosis, or chronic liver disease;

  • low blood cell counts;

  • a weak immune system or bone marrow disorder; or

  • if you are pregnant or breastfeeding.

Methotrexate is sometimes used to treat cancer in people who have a condition listed above. Your doctor will decide if this treatment is right for you.

Tell your doctor if you have ever had:

Methotrexate is sometimes used to treat cancer during pregnancy. However, methotrexate may cause injury or death to an unborn baby and should not be used during pregnancy to treat arthritis or psoriasis. Tell your doctor if you are pregnant.

Methotrexate can harm an unborn baby if the mother or the father is using methotrexate.

  • If you are a woman, you may need a pregnancy test before starting this treatment. Use effective birth control to prevent pregnancy while you are using methotrexate and for at least 6 months after your last dose.

  • If you are a man, use effective birth control if your sex partner is able to get pregnant. Keep using birth control for at least 3 months after your last dose.

  • Tell your doctor right away if a pregnancy occurs while either the mother or the father is using methotrexate.

This medicine may affect fertility (ability to have children) in both men and women. However, it is important to use birth control to prevent pregnancy because methotrexate may harm the baby if a pregnancy does occur.

Do not breastfeed while using this medicine.

Do not give this medicine to a child without medical advice.

How is methotrexate injection given?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Methotrexate is usually given once per week. You must use the correct dose. Some people have died after incorrectly using methotrexate every day.

Methotrexate is injected into a muscle, under the skin, or as an infusion into a vein. A healthcare provider will give you this injection and may teach you how to properly use the medication by yourself.

Methotrexate may also be injected by a healthcare provider directly into a joint, or into the space around your spinal cord.

Read and carefully follow any Instructions for Use provided with your medicine. You may need to mix methotrexate with a liquid (diluent) before using it. Ask your doctor or pharmacist if you don't understand all instructions.

Prepare an injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Methotrexate can be toxic to your organs, and may lower your blood cell counts. You will need frequent medical tests, and you may need an occasional liver biopsy or chest X-ray. Your cancer treatments may be delayed based on the results.

If you need to be sedated for dental work, tell your dentist you currently use methotrexate.

Store methotrexate in its original packaging at room temperature away from moisture, heat, and light. Do not freeze.

A single-use vial (bottle) or auto-injector is for one use only. Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your methotrexate injection, or if you forget to use the medicine at home.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of methotrexate injection can be fatal.

What should I avoid while receiving methotrexate injection?

Avoid exposure to sunlight or artificial UV rays (sunlamps, tanning beds, or PUVA treatment), especially if you have psoriasis. Methotrexate can make your skin more sensitive to sunlight and your psoriasis may worsen.

Avoid drinking alcohol. It may increase your risk of liver damage.

Do not receive a "live" vaccine while using methotrexate, or you could develop a serious infection. Live vaccines include measles, mumps, rubella (MMR), rotavirus, typhoid, yellow fever, varicella (chickenpox), zoster (shingles), and nasal flu (influenza) vaccine.

Methotrexate may impair your thinking or reactions. Avoid driving or operating machinery until you know how methotrexate will affect you.

Methotrexate injection side effects

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).

Methotrexate can cause serious or fatal side effects. Call your doctor at once if you have:

  • sudden chest pain, wheezing, dry cough, cough with mucus, feeling short of breath;

  • swollen lymph glands, night sweats, weight loss;

  • blisters or ulcers in your mouth, red or swollen gums, trouble swallowing;

  • vomiting, diarrhea, blood in your urine or stools;

  • skin changes such as redness, warmth, swelling, or oozing;

  • low blood cell counts--fever, chills, bruising or bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath;

  • kidney problems--little or no urination, swelling in your feet or ankles;

  • liver problems--swelling around your midsection, right-sided upper stomach pain, nausea, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes);

  • nerve problems--confusion, weakness, drowsiness, coordination problems, feeling irritable, headache, neck stiffness, vision problems, loss of movement in any part of your body, seizure; or

  • signs of tumor cell breakdown--tiredness, muscle cramps, nausea, vomiting, diarrhea, fast or slow heart rate, tingling in your hands and feet or around your mouth.

Common side effects may include:

  • fever, chills, tiredness, not feeling well;

  • low blood cell counts;

  • cough, chest tightness, trouble breathing;

  • mouth sores;

  • headache, dizziness;

  • nausea, vomiting, stomach pain, indigestion, diarrhea;

  • abnormal liver function tests;

  • runny or stuffy nose, sore throat;

  • rash, hair loss, burning skin lesions; or

  • being more sensitive to light.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect methotrexate injection?

Methotrexate can harm your liver, especially if you also use certain medicines for infections, tuberculosis, birth control, hormone replacement, high cholesterol, heart problems, high blood pressure, seizures, pain, or arthritis (including Tylenol, Advil, Motrin, or Aleve).

Tell your doctor about all your other medicines, especially:

This list is not complete and many other drugs may affect methotrexate. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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