Leflunomide (By mouth)
Treats rheumatoid arthritis in adults.
When This Medicine Should Not Be Used
How to Use This Medicine
- Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
If a dose is missed:
- Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
- Keep all medicine out of the reach of children. 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 activated charcoal, cholestyramine (Questran®), methotrexate (Folex®, Rheumatrex®), rifampin (Rifadin®, Rimactane®), or a blood thinner (such as warfarin, Coumadin®).
- This medicine may interfere with vaccines. Ask your doctor before you get a flu shot or any other vaccines. Live virus vaccines should not be given while receiving this medicine.
Warnings While Using This Medicine
- This medicine may cause birth defects if either partner is using it during conception or pregnancy. Tell your doctor right away if you or your partner becomes pregnant. Use an effective form of birth control to keep from getting pregnant. A man intending to father a child should stop taking this medicine and check with his doctor right away.
- Make sure your doctor knows if you have kidney disease, liver disease (including hepatitis B or C), diabetes, a severe or untreated infection, lung disease, nerve problems, a history of tuberculosis, or a history of blood or bone marrow problems.
- Serious skin reactions can occur with this medicine. Stop using this medicine and check with your doctor right away if you have any of the following symptoms while taking this medicine: blistering, peeling, or loosening of the skin; chills; itching; joint or muscle pain; 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.
- Liver problems may occur while you are using this medicine. Stop using this medicine and check with your doctor right away if you are having more than one of these symptoms: abdominal or stomach pain or tenderness; clay-colored stools; dark urine; decreased appetite; fever; headache; loss of appetite; nausea or vomiting; skin rash; swelling of the feet or lower legs; unusual tiredness or weakness; or yellow eyes or skin.
- This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Avoid people who are ill, and wash your hands often. Brush and floss your teeth gently, do not play rough sports, and be careful with sharp objects.
- Check with your doctor right away if you have a cough with or without a fever, shortness of breath, or any difficulty with breathing.
- You will need to have a skin test for tuberculosis before you start using this medicine. Tell your doctor if you or anyone in your home has ever had a positive reaction to a tuberculosis test.
- Using this medicine may increase your risk of getting serious infections or cancer. Talk to your doctor if you have concerns about this risk.
- Stop using this medicine and check with your doctor right away if you are having burning, numbness, tingling, or painful sensations in the arms, hands, legs, or feet. These could be symptoms of a condition called peripheral neuropathy.
- You will need to have your blood pressure measured before starting this medicine and while you are using it. If you notice any change to your recommended blood pressure, call your doctor right away. If you have questions about this, talk to your doctor.
- Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
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.
- Dark-colored urine or pale stools.
- Fast, pounding, or uneven heartbeat.
- Fever, chills, cough, sore throat, and body aches.
- Nausea, vomiting, loss of appetite, or pain in your upper stomach.
- Numbness, tingling, or burning pain in your hands, arms, legs, or feet.
- Shortness of breath, troubled breathing, or wheezing.
- Unusual bleeding, bruising, or weakness.
- Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
- Back pain.
- Diarrhea, stomach pain or upset.
- Hair loss.
- Lack or loss of strength.
- Mild skin rash.
- Stuffy or runny nose.
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
- Last reviewed on 8/4/2014
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