Methotrexate has rarely caused serious (sometimes fatal) side effects. Therefore, this medication should be used only to treat severe diseases caused by an overactive immune system (such as psoriasis, rheumatoid arthritis).
Methotrexate has caused birth defects and death in unborn babies. Women must avoid becoming pregnant while using this medication. Pregnant women who have psoriasis or rheumatoid arthritis must not use methotrexate. (See also Precautions section.)
Methotrexate (usually at high dosages) has rarely caused severe (sometimes fatal) blood/bone marrow problems (decreasing your body's ability to fight infections) and stomach/intestinal disease (such as bleeding) when used at the same time as non-steroidal anti-inflammatory drugs (NSAIDs such as indomethacin, ketoprofen). Therefore, NSAIDs should not be used with high-dose methotrexate. Caution is advised if you also take aspirin. NSAIDs/aspirin may be used with low-dose methotrexate such as for the treatment of rheumatoid arthritis if directed by your doctor. If your doctor has directed you to take low-dose aspirin for heart attack or stroke prevention (usually at dosages of 81-325 milligrams a day), you should continue taking it unless your doctor instructs you otherwise. Ask your doctor or pharmacist for more details on the safe use of these drugs (such as close monitoring by your doctor, keeping the same doses of NSAIDs).
Methotrexate use has rarely caused serious (sometimes fatal) side effects, such as lung problems, lung infections (Pneumocystis jiroveci pneumonia), skin reactions, diarrhea, and mouth sores (ulcerative stomatitis). (See also Side Effects section.)
Lumps (tumors/abnormal growths) may very rarely appear during methotrexate use. The drug must be stopped and treatment may be needed. Tell your doctor right away if new lumps/growths occur.
When used to treat tumors, methotrexate sometimes causes side effects due to the rapid destruction of cancer cells (tumor lysis syndrome). To lower your risk, drink plenty of fluids unless your doctor directs you otherwise. Also, your doctor may prescribe an additional medication. Tell your doctor right away if you have symptoms such as irregular heartbeat, low back/side pain, signs of kidney problems (such as pink/bloody urine, change in the amount of urine, painful urination), or muscle spasms/weakness.
When this medication is used with radiation treatment, it may rarely increase the risk of tissue and bone damage. Discuss the risks and benefits of your treatment with your doctor.Who should not take Methotrexate (PF) Auto-Injector?
Methotrexate is used to control severe psoriasis or rheumatoid arthritis that has not responded to other treatments. It may also be used to control juvenile rheumatoid arthritis. Methotrexate belongs to a class of drugs known as antimetabolites. It works by suppressing the immune system.
Read the Patient Information Leaflet and Instructions for Use if available from your pharmacist before you start using methotrexate and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Inject this medication under the skin as directed by your doctor, usually once a week. Do not rub the area after injection.
Before injecting each dose, clean the injection site with rubbing alcohol. Change the injection site each time to lessen injury under the skin. Methotrexate may be injected into the stomach area and thigh only. Do not inject within 2 inches (5 centimeters) of the belly button. Do not inject into other areas of the body. Do not inject into skin that is red, swollen, or bruised, or into areas with scars/stretch marks.
Learn how to store and discard medical supplies safely.
The dosage is based on your medical condition and response to treatment.
Use this medication regularly to get the most benefit from it. To help you remember, use it on the same day each week.
Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of side effects will increase.
It may take up to several months before you get the full benefit of this drug.
Tell your doctor if your condition does not improve or if it worsens.
See also Warning section.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including: mouth sores, diarrhea, signs of anemia (such as unusual tiredness, pale skin), signs of liver problems (such as dark urine, persistent nausea/vomiting, stomach/abdominal pain, yellowing eyes/skin), easy bruising/bleeding, black stools, enlarged glands/lymph nodes, bone pain, unusual pain and discoloration of the skin, signs of kidney problems (such as change in the amount of urine), dry cough, muscle weakness.
Get medical help right away if you have any very serious side effects, including: irregular heartbeat, vision changes, weakness on one side of the body, severe headache, neck stiffness, mental/mood changes, seizures.
This medication may lower your ability to fight infections. This may make you more likely to get a serious (rarely fatal) infection or make any infection you have worse. Tell your doctor right away if you have any signs of infection (such as fever, chills, persistent sore throat, cough).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
See also Warning section.
Before using methotrexate, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease, kidney disease, lung disease (such as pulmonary fibrosis), alcohol use, suppressed immune system, blood cell/bone marrow disorders, certain stomach/intestinal diseases (such as peptic ulcer, ulcerative colitis), any active infection (including chickenpox or recent exposure to it), folic acid deficiency.
Methotrexate can make you more likely to get infections or may worsen any current infections. Therefore, wash your hands well to prevent the spread of infection. Avoid contact with people who have infections that may spread to others (such as chickenpox, measles, flu). Consult your doctor if you have been exposed to an infection or for more details.
To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.
This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Avoid alcoholic beverages.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Children may be more sensitive to the side effects of this drug, especially seizures.
This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness.
Methotrexate must not be used during pregnancy. It may harm an unborn baby. It is important to prevent pregnancy during and after treatment with methotrexate. Therefore, males and females must use reliable forms of birth control (such as condoms, birth control pills) during treatment. Males should continue to use birth control for at least 3 months after the end of treatment. Females should continue to use birth control for at least 1 menstrual cycle after the end of treatment. If you become pregnant or think you may be pregnant, tell your doctor right away.
See also Warning section.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: acitretin, asparaginase, chloramphenicol, leflunomide, other drugs that can cause kidney problems (such as cisplatin), other drugs that can cause liver problems (such as azathioprine, sulfasalazine, retinoids such as isotretinoin), penicillins, phenytoin, probenecid, procarbazine, pyrimethamine, sulfa medications, tetracyclines.
Certain drugs that reduce stomach acid (proton pump inhibitors-PPIs such as esomeprazole, omeprazole, pantoprazole) may increase the amount of methotrexate in your blood. This effect may increase the risk of side effects, especially with high-dose methotrexate treatment. Ask your doctor or pharmacist for details and ways to lessen the risk of side effects.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include severe nausea and vomiting, and bloody stools.
Laboratory and/or medical tests (such as complete blood cell counts, liver and kidney function tests, pregnancy test, chest X-ray) should be performed before you start treatment, periodically to monitor your progress, or to check for side effects. Consult your doctor for more details.
For the best possible benefit, it is important to receive each scheduled dose of this medication as directed. If you miss a dose, contact your doctor or pharmacist right away to establish a new dosing schedule. Do not double the dose to catch up.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.Information last revised October 2016. Copyright(c) 2016 First Databank, Inc.
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