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Leflunomide Dosage

The information at is not a substitute for medical advice. ALWAYS consult your doctor or pharmacist.

Usual Adult Dose for:

Additional dosage information:

Usual Adult Dose for Rheumatoid Arthritis

Loading dose: 100 mg once daily for 3 days.

Maintenance: 10 to 20 mg daily.

Study (n=263)
100 mg per day for 2 days, followed by 10 mg leflunomide daily in combination with methotrexate (10 to 15 mg/week or 15 to 20 mg/week), and folate 1 mg/day.

Renal Dose Adjustments

Leflunomide should be used with caution in patients with renal insufficiency.

Liver Dose Adjustments

In patients with significant liver disease, leflunomide is not recommended.

Dosage reduction or discontinuation is based on monitoring of ALT levels. For ALT elevations between 2- and 3-fold upper limit of normal (ULN), reduce dose to 10 mg per day. If elevation persists despite dose reduction or if ALT elevations of greater than 3-fold ULN are present, discontinue leflunomide and administer cholestyramine or charcoal.

Dose Adjustments

Reduced dosage may be necessary in patients with mild or moderate adverse reactions.


The safety and effectiveness in pediatric patients (less than 18 years of age) with polyarticular course juvenile rheumatoid arthritis (JRA) have not been fully evaluated.


Studies have indicated that the active metabolite of leflunomide (M1) is not removed by hemodialysis.

Other Comments

The primary active metabolite of leflunomide (M1) has a very long half-life of approximately 2 weeks.

Do not exceed doses of 20 mg per day. Small studies (n=104) have shown a greater incidence of side effects at 25 mg daily doses.

Baseline levels for platelets, white blood cell count and hemoglobin or hematocrit should be obtained on all patients beginning leflunomide therapy, and then monthly for the first six months following initiation of therapy and every 6 to 8 weeks thereafter.

In the event of any serious toxicity from leflunomide, including hypersensitivity, the drug should be stopped, and a drug elimination procedure should be started. After stopping treatment with leflunomide, the manufacturer recommends the use of cholestyramine 8 grams three times daily for 11 days. Plasma leflunomide levels should be measured by two separate tests at least 14 days apart. If plasma levels are higher than 0.02 mg/L, additional cholestyramine treatment should be considered. Without the drug elimination procedure, it may take up to 2 years to reach plasma metabolite levels less than 0.02 mg/L due to individual variation in drug clearance.