Leflunomide

DRUG INFORMATION

  ADULT
    - Loading dosage for patients at low risk for leflunomide tablets-associated
      hepatotoxicity and leflunomide tablets-associated myelosuppression: 100 mg daily
      for 3 days.
      Source: US FDA label for leflunomide (Leflunomide), section 'dosage and
      administration', retrieved 2026-08-29
    - ( 2.1 ) Maintenance dosage: 20 mg daily.
      Source: US FDA label for leflunomide (Leflunomide), section 'dosage and
      administration', retrieved 2026-08-29
    - ( 2.1 ) Maximum recommended daily dosage: 20 mg once daily.
      Source: US FDA label for leflunomide (Leflunomide), section 'dosage and
      administration', retrieved 2026-08-29

  CHILD
    - The safety and effectiveness of leflunomide in pediatric patients have not been
      established. The safety and effectiveness of leflunomide in the treatment of
      polyarticular course juvenile idiopathic arthritis (JIA) was evaluated in a single
      multicenter, double-blind, active-controlled trial in 94 pediatric patients (1:1
      randomization) with polyarticular course juvenile idiopathic arthritis (JIA) as
      defined by the American College of Rheumatology (ACR).
      Source: US FDA label for leflunomide (Leflunomide), section 'pediatric use',
      retrieved 2026-08-29

  RENAL IMPAIRMENT
    - Given the need to metabolize leflunomide into the active species, the role of the
      liver in drug elimination/recycling, and the possible risk of increased hepatic
      toxicity, the use of leflunomide in patients with hepatic impairment is not
      recommended. 8.7 Renal Impairment Dedicated studies of the effect of renal
      impairment on leflunomide pharmacokinetics have not been conducted.
      Source: US FDA label for leflunomide (Leflunomide), section 'use in specific
      populations', retrieved 2026-08-29

  HEPATIC IMPAIRMENT
    - No dosage adjustment is needed in patients over 65. 8.6 Hepatic Impairment
      Dedicated studies of the effect of hepatic impairment on leflunomide
      pharmacokinetics have not been conducted.
      Source: US FDA label for leflunomide (Leflunomide), section 'use in specific
      populations', retrieved 2026-08-29
    - Given the need to metabolize leflunomide into the active species, the role of the
      liver in drug elimination/recycling, and the possible risk of increased hepatic
      toxicity, the use of leflunomide in patients with hepatic impairment is not
      recommended. 8.7 Renal Impairment Dedicated studies of the effect of renal
      impairment on leflunomide pharmacokinetics have not been conducted.
      Source: US FDA label for leflunomide (Leflunomide), section 'use in specific
      populations', retrieved 2026-08-29
    - Based on animal data, human plasma concentrations of teriflunomide of less than
      0.02 mg/L (0.02 mcg/mL) are expected to have minimal embryo-fetal risk [see
      Contraindications (4) , Warnings and Precautions (5.3), and Use in Specific
      Populations (8.1) ] . 5.2 Hepatotoxicity Severe liver injury, including fatal
      liver failure, has been reported in some patients treated with leflunomide.
      Source: US FDA label for leflunomide (Leflunomide), section 'warnings and
      cautions', retrieved 2026-08-29

  PREGNANCY   [ AVOID ]
    The label says not to use it. Read the quote below before deciding.
    - Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors
      pregnancy outcomes in women exposed to leflunomide during pregnancy.
      Source: US FDA label for leflunomide (Leflunomide), section 'pregnancy', retrieved
      2026-08-29
    - Health care providers and patients are encouraged to report pregnancies by calling
      1-877-311-8972 or visit http://www.pregnancystudies.org/participate-in-a-study/.
      Source: US FDA label for leflunomide (Leflunomide), section 'pregnancy', retrieved
      2026-08-29
    - Risk Summary Leflunomide is contraindicated for use in pregnant women because of
      the potential for fetal harm.
      Source: US FDA label for leflunomide (Leflunomide), section 'pregnancy', retrieved
      2026-08-29

  BREASTFEEDING
    - Leflunomide may cause fetal harm when administered during pregnancy.
      Source: US FDA label for leflunomide (Leflunomide), section 'nursing mothers',
      retrieved 2026-08-29
    - Advise females of the potential risk to the fetus.
      Source: US FDA label for leflunomide (Leflunomide), section 'nursing mothers',
      retrieved 2026-08-29
    - Advise females to notify their healthcare provider immediately if pregnancy occurs
      or is suspected during treatment [see Use in Specific Populations (8.1)] .
      Source: US FDA label for leflunomide (Leflunomide), section 'nursing mothers',
      retrieved 2026-08-29