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Leflunomide oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.




WARNING: Pregnancy must be excluded before the start of treatment with leflunomide. This drug must not be used during pregnancy, nor by women of childbearing age who are not using reliable birth control (contraception). Unless female leflunomide users go through a certain process to eliminate this drug from their body, pregnancy must be avoided for 2 years after this drug has been stopped.


This medication is used to treat arthritis (rheumatoid type). It works by suppressing your immune system, since rheumatoid arthritis is caused by damage from an overactive immune system.

How To Use

This drug is taken by mouth, generally once daily. Follow directions carefully, as it is generally recommended to start with a special higher dose for the first 3 days, then decrease to the regular dose thereafter. Dosing is based on your medical conditions, response to therapy, and liver function test results. After treatment is stopped, cholestyramine may be given as directed, generally three times daily for 11 days. This procedure is used if you require a rapid removal of the drug from your system. Without the procedure the drug may persist for 2 years. Consult your doctor or pharmacist to learn whether you are a candidate for cholestyramine treatment (such as a couple planning to have children).

Side Effects

Nausea, diarrhea, flu-like symptoms, mild dizziness, headache may occur. If these effects persist or worsen, notify your doctor promptly. Tell your doctor immediately if any of the following unlikely but serious side effects occur: hair loss, chest pain, back pain, mouth sores, muscle cramping, numbness/tingling sensations. Tell your doctor immediately if any of the following highly unlikely but very serious side effects occur: unusual lumps (lymph gland enlargement). Leflunomide has rarely caused serious (possibly fatal) infections and blood disorders due to suppressing the bone marrow and immune system. Tell your doctor immediately if signs of infection (such as fever), extreme weakness/fatigue, or easy bruising/bleeding develop. Leflunomide may need to be stopped. The elimination procedure using cholestyramine or charcoal may be required (see How to Use section). Consult your doctor or pharmacist for more details. Leflunomide has rarely caused serious (possibly fatal) liver disease, especially in people with other risks for liver disease. Tell your doctor immediately if persistent nausea or vomiting, stomach/abdominal pain, dark urine, or yellowing eyes/skin develop. Leflunomide may need to be stopped. The elimination procedure using cholestyramine or charcoal may be required (see How to Use section). Consult your doctor or pharmacist for more details. In the unlikely event you have an allergic reaction to this drug, seek immediate medical attention. Symptoms of an allergic reaction include: rash, itching, swelling, severe dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.


This medication should not be used if you have certain medical conditions. Before using this medication, consult your doctor or pharmacist if you have: a severe immune system disorder, bone marrow problems (dysplasia), uncontrolled infections. Tell your doctor your medical history, including: any allergies, kidney or liver diseases, blood disorders. Vaccination with live vaccine products while using this drug is not recommended. Consult your doctor. Due to possible fetal harm or death, a pregnancy test is needed before starting treatment. Use of reliable birth control is necessary. Consult your doctor. This drug must not be used during pregnancy. If you become pregnant or think you may be pregnant, inform your doctor immediately. It is not known whether this drug passes into breast milk. Because of the potential risk to the infant, breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding. To minimize risk, men wishing to father a child should consider stopping this drug and using cholestyramine as directed (see How To Use). Consult your doctor. Use of this drug in children/teenagers under 18 years of age is not recommended.

Drug Interactions

Tell your doctor of all nonprescription and prescription medication you may use, especially: cholestyramine, drugs affecting the liver (e.g., methotrexate, troglitazone), rifamycins (e.g., rifampin), drugs which depress the immune system (e.g., prednisone, cyclosporine). Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Do not share this medication with others. Laboratory and/or medical tests (e.g., liver function and blood counts-CBC/platelets) will be performed periodically to monitor your progress and check for side effects, especially if you are using this drug in combination with methotrexate.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15-30 degrees C) away from light and moisture.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).