Medically reviewed by Drugs.com. Last updated on Sep 9, 2023.
- Very bad side effects like bone marrow problems, liver problems, lung problems, infections, and skin reactions (Stevens-Johnson syndrome/toxic epidermal necrolysis) can happen with methotrexate injection (subcutaneous). Some side effects may not go away and can be deadly. You must talk with the doctor about the risks of methotrexate injection (subcutaneous).
- This medicine may cause kidney problems in some patients. Talk with the doctor.
- Regular blood work and other exams will need to be done to check for side effects. Follow what the doctor has told you.
- Tell your doctor if you have kidney problems or extra fluid around your stomach area or lungs. The chance of side effects may be raised.
- Very bad and sometimes deadly bone marrow problems and stomach or bowel problems have happened when methotrexate injection (subcutaneous) was taken with NSAIDs like ibuprofen or naproxen. Talk with the doctor.
- This medicine may raise your chance of lymphoma and other cancers.
- Patients with cancer may be at greater risk of getting a bad and sometimes deadly health problem called tumor lysis syndrome (TLS). Talk with the doctor.
- Tell your doctor if you get diarrhea or mouth or tongue sores or irritation. You may need to stop methotrexate injection (subcutaneous). Severe and sometimes deadly bowel problems may happen.
- Talk with your doctor if you are getting radiation. There may be more chance of harm to tissue and bone.
- Not all methotrexate products are used to treat cancer. Talk with the doctor.
- This medicine may cause harm to an unborn baby or loss of an unborn baby. A pregnancy test will be done before you start methotrexate injection (subcutaneous) to show that you are NOT pregnant.
- Women must use birth control while taking methotrexate injection (subcutaneous) and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
- Men with a partner who may get pregnant must use birth control while taking methotrexate injection (subcutaneous) and for some time after the last dose. Ask your doctor how long to use birth control. If your partner gets pregnant, call the doctor right away.
- Do not take if you are pregnant.
- This medicine must only be used when other drugs cannot be used or have not worked. Talk with your doctor to be sure that the benefits of methotrexate injection (subcutaneous) are more than the risks.
Uses of Methotrexate Injection:
- It is used to treat some types of arthritis.
- It is used to treat psoriasis.
- It may be given to you for other reasons. Talk with the doctor.
What do I need to tell my doctor BEFORE I take Methotrexate Injection?
- If you are allergic to methotrexate injection (subcutaneous); any part of methotrexate injection (subcutaneous); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have any of these health problems: Bone marrow disease (like low white blood cell count, low platelet count, or anemia), drinking problem, liver disease, or a weak immune system.
- If you are breast-feeding. Do not breast-feed while you take methotrexate injection (subcutaneous). You may also need to avoid breast-feeding for some time after your last dose. Talk with your doctor to see if you need to avoid breast-feeding after your last dose.
This is not a list of all drugs or health problems that interact with methotrexate injection (subcutaneous).
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take methotrexate injection (subcutaneous) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take Methotrexate Injection?
- Tell all of your health care providers that you take methotrexate injection (subcutaneous). This includes your doctors, nurses, pharmacists, and dentists.
- Avoid driving and doing other tasks or actions that call for you to be alert until you see how methotrexate injection (subcutaneous) affects you.
- You may have more chance of getting an infection. Wash hands often. Stay away from people with infections, colds, or flu.
- You may bleed more easily. Be careful and avoid injury. Use a soft toothbrush and an electric razor.
- Talk with your doctor before getting any vaccines. Use of some vaccines with methotrexate injection (subcutaneous) may either raise the chance of an infection or make the vaccine not work as well.
- Avoid drinking alcohol while taking methotrexate injection (subcutaneous).
- You may get sunburned more easily. Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun. Keep protecting yourself from sunburn for as long as you were told by your doctor.
- Tell your doctor if you have too much sweat, fluid loss, throwing up, diarrhea, not hungry, or more thirst.
- A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
- If you are 65 or older, use methotrexate injection (subcutaneous) with care. You could have more side effects.
- This medicine may affect fertility. This may lead to not being able to get pregnant or father a child. If this happens, it is not known if fertility will go back to normal.
- If you are a woman and you miss a period, have unprotected sex, or think that your birth control has not worked, call your doctor right away.
How is this medicine (Methotrexate Injection) best taken?
Use methotrexate injection (subcutaneous) as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- It is given as a shot into the fatty part of the skin on the top of the thigh or the belly area.
- If you will be giving yourself the shot, your doctor or nurse will teach you how to give the shot.
- Do not give into skin within 2 inches of the belly button.
- Do not use if the solution is cloudy, leaking, or has particles.
- Do not give into skin that is irritated, tender, bruised, red, scaly, hard, scarred, or has stretch marks.
- If you are not sure if your dose was injected or if you have a hard time giving the dose, talk with your doctor or pharmacist before using another dose.
- Throw away needles in a needle/sharp disposal box. Do not reuse needles or other items. When the box is full, follow all local rules for getting rid of it. Talk with a doctor or pharmacist if you have any questions.
- Take as you have been told by your doctor. This medicine is not to be used every day. Be sure you know how to use methotrexate injection (subcutaneous).
- How methotrexate injection (subcutaneous) is taken may change based on blood work results, side effects, and how well the drug is working.
- You will need to take special care when handling methotrexate injection (subcutaneous). Check with the doctor or pharmacist to see how to handle methotrexate injection (subcutaneous).
- Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.
What do I do if I miss a dose?
- Call your doctor to find out what to do.
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of infection like fever, chills, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or wound that will not heal.
- Signs of bleeding like throwing up or coughing up blood; vomit that looks like coffee grounds; blood in the urine; black, red, or tarry stools; bleeding from the gums; abnormal vaginal bleeding; bruises without a cause or that get bigger; or bleeding you cannot stop.
- Signs of a pancreas problem (pancreatitis) like very bad stomach pain, very bad back pain, or very bad upset stomach or throwing up.
- Signs of kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
- Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- Signs of lung or breathing problems like shortness of breath or other trouble breathing, cough, or fever.
- Signs of nerve problems like a burning, numbness, or tingling feeling that is not normal; weakness; or not being able to move a part of the body (paralysis).
- Pinpoint red spots on the skin.
- Very bad dizziness or passing out.
- Feeling confused.
- Feeling sleepy.
- Change in eyesight.
- Bone pain.
- Swelling, warmth, numbness, change of color, or pain in a leg or arm.
- Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight.
- Neck stiffness.
What are some other side effects of Methotrexate Injection?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Upset stomach or throwing up.
- Not hungry.
- Hair loss.
- Feeling dizzy, tired, or weak.
- Stomach pain.
- Signs of a common cold.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
If OVERDOSE is suspected:
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
How do I store and/or throw out Methotrexate Injection?
- Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.
- Do not freeze.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
Consumer Information Use and Disclaimer
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else's drugs.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about methotrexate injection (subcutaneous), please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
Frequently asked questions
- Why should I take folic acid with methotrexate?
- How do I know if methotrexate is working for rheumatoid arthritis?
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- How long does it take to work?
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