Leflunomide: uses, dosing, side effects & brands
Leflunomide is an antirheumatic agent sold in the U.S. under one brand, for rheumatoid arthritis. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Antirheumatic Agent
- Treats
- Rheumatoid Arthritis
- Available as
- Tablet
- Sold as
- Arava
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
- What the pharmacy pays
- about $9 for a 30-count supply — not your price
- Boxed warning
- Boxed warning
How leflunomide is dosed
From the FDA label for Arava (application NDA020905). Other leflunomide products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Loading dosage for patients at low risk for ARAVA-associated hepatotoxicity and ARAVA-associated myelosuppression: 100 mg daily for 3 days. ( 2.1 ) Maintenance dosage: 20 mg daily. ( 2.1 ) Maximum recommended daily dosage: 20 mg once daily. ( 2.1 ) If 20 mg once daily is not tolerated, may decrease dosage to 10 mg once daily. ( 2.1 ) Screen patients for active and latent tuberculosis, pregnancy test (females), blood pressure, and laboratory tests before starting ARAVA. ( 2.2 ) 2.1 Recommended Dosage The recommended dosage of ARAVA is 20 mg once daily. Treatment may be initiated with or without a loading dose, depending upon the patient's risk of ARAVA-associated hepatotoxicity and ARAVA-associated myelosuppression. The loading dose provides steady-state concentrations more rapidly. For patients who are at low risk for ARAVA-associated hepatotoxicity and ARAVA-associated myelosuppression, the recommended ARAVA loading dose is 100 mg once daily for 3 days. Subsequently administer 20 mg once daily. For patients at high risk for ARAVA-associated hepatotoxicity (e.g., those taking concomitant methotrexate) or ARAVA-associated myelosuppression (e.g., patients taking concomitant immunosuppressants), the recommended ARAVA dosage is 20 mg once daily without a loading dose [see Warnings and Precautions (5.2 , 5.4) ] . The maximum recommended daily dose is 20 mg once per day. Consider…
Leflunomide side effects
The following serious adverse reactions are described elsewhere in the labeling: Hepatotoxicity [see Warnings and Precautions (5.2) ] Immunosuppression [see Warnings and Precautions (5.4) ] Bone marrow suppression [see Warnings and Precautions (5.4) ] Serious infections [see Warnings and Precautions (5.4) ] Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reactions with eosinophilia and systemic symptoms [see Warnings and Precautions (5.5) ] Skin ulcers [see Warnings and Precautions (5.6) ] Peripheral neuropathy [see Warnings and Precautions (5.8) ] Interstitial lung disease [see Warnings and Precautions (5.9) ] The most commonly reported adverse reactions (≥10%) regardless of relation to ARAVA treatment were diarrhea, respiratory infection, nausea, headache, rash, abnormal liver enzymes, and dyspepsia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact sanofi-aventis U.S. LLC at 1-800-633-1610 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice. In clinical studies (Trials 1, 2, and 3), 1,865 patients were treated with ARAVA administered as either monotherapy or in…
Who shouldn’t take leflunomide
ARAVA is contraindicated in: Pregnant women. ARAVA may cause fetal harm. If a woman becomes pregnant while taking this drug, stop ARAVA, apprise the patient of the potential hazard to the fetus, and begin a drug elimination procedure [see Warnings and Precautions (5.1 , 5.3) and Use in Specific Populations (8.1) ] . Patients with severe hepatic impairment [see Warnings and Precautions (5.2) ] . Patients with known hypersensitivity to leflunomide or any of the other components of ARAVA. Known reactions include anaphylaxis [see Adverse Reactions (6.1) ] . Patients being treated with teriflunomide [see Drug Interactions (7) ] . Pregnancy. ( 4 , 5.1 , 8.1 ) Severe hepatic impairment. ( 4 , 5.2 ) Hypersensitivity to ARAVA or any of its inactive components. ( 4 ) Current teriflunomide treatment. ( 4 )
Leflunomide drug interactions
Following oral administration, leflunomide is metabolized to an active metabolite, teriflunomide, which is responsible for essentially all of leflunomide's in vivo activity. Drug interaction studies have been conducted with both ARAVA (leflunomide) and with its active metabolite, teriflunomide, where the metabolite was directly administered to the test subjects. Drugs metabolized by CYP2C8 and OAT3 transporters: Monitor patients because teriflunomide may increase exposure of these drugs. ( 7 ) Teriflunomide may increase exposure of ethinylestradiol and levonorgestrel. Choose an appropriate oral contraceptive. ( 7 ) Drugs metabolized by CYP1A2: Monitor patients because teriflunomide may decrease exposure of these drugs. ( 7 ) Warfarin: Monitor INR as teriflunomide may decrease INR. ( 7 ) Drugs metabolized by BCRP and OATP1B1/B3 transporters: Monitor patients because teriflunomide may increase exposure of these drugs. ( 7 ) Rosuvastatin: The dose of rosuvastatin should not exceed 10 mg once daily in patients taking ARAVA. ( 7 ) Effect of Potent CYP and Transporter Inducers Leflunomide is metabolized by CYP450 metabolizing enzymes. Concomitant use of ARAVA and rifampin, a potent inducer of CYP and transporters, increased the plasma concentration of teriflunomide by 40%. However, when coadministered with the metabolite, teriflunomide, rifampin did not affect its pharmacokinetics. No dosage adjustment is recommended for ARAVA when coadministered with rifampin. Because of the potential for ARAVA concentrations to continue to increase with multiple dosing, caution should be used if patients are to be receiving both ARAVA and rifampin [see Clinical Pharmacology (12.3) ] . Effect on CYP2C8 Substrates Teriflunomide is an inhibitor of CYP2C8 in vivo . In patients taking ARAVA, exposure of drugs metabolized by CYP2C8 (e.g., paclitaxel, pioglitazone, repaglinide, rosiglitazone) may be increased. Monitor these patients and adjust the dose of the concomitant drug(s) metabolized by CYP2C8 as required [see Clinical Pharmacology (12.3) ] . Effect on Warfarin Coadministration of ARAVA with warfarin requires close monitoring of the international normalized ratio (INR) because teriflunomide, the active metabolite of ARAVA, may decrease peak INR by approximately 25%. Effect on Oral Contraceptives Teriflunomide may increase the systemic exposures of ethinylestradiol and levonorgestrel. Consideration should be given to the type or dose of contraceptives used in combination with ARAVA [see Clinical Pharmacology (12.3) ] . Effect on CYP1A2 Substrates Teriflunomide, the active metabolite of ARAVA, may be a weak inducer of CYP1A2 in vivo . In patients taking ARAVA, exposure of drugs metabolized by CYP1A2 (e.g., alosetron, duloxetine, theophylline, tizanidine) may be reduced. Monitor these patients and adjust the dose of the concomitant drug(s) metabolized by CYP1A2 as required [see Clinical Pharmacology (12.3) ] . Effect on Organic Anion Transporter 3 (OAT3) Substrates Teriflunomide inhibits the activity of OAT3 in vivo . In patients taking ARAVA, exposure of drugs which are OAT3 substrates (e.g., cefaclor, cimetidine, ciprofloxacin, penicillin G, ketoprofen, furosemide, methotrexate, zidovudine) may be increased. Monitor these patients and adjust the dose of the concomitant drug(s) which are OAT3 substrates as required [see Clinical Pharmacology (12.3) ] . Effect on BCRP and Organic Anion Transporting Polypeptide B1 and B3 (OATP1B1/1B3) Substrates Teriflunomide inhibits the activity of BCRP and OATP1B1/1B3 in vivo . For a patient taking ARAVA, the dose of rosuvastatin should not exceed 10 mg once daily. For other substrates of BCRP (e.g., mitoxantrone) and drugs in the OATP family (e.g., methotrexate, rifampin), especially HMG-Co reductase inhibitors (e.g., atorvastatin, nateglinide, pravastatin, repaglinide, and simvastatin), consider reducing the dose of these drugs and monitor patients closely for signs and symptoms of increased exposures to the drugs while patients are taking ARAVA [see Clinical Pharmacology (12.3) ] .
Every leflunomide product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Arava.
What leflunomide pills look like
Imprint codes, colour and shape from the FDA’s labelling data. Match the imprint on your pill — or search any imprint.
Leflunomide and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for leflunomide: levels in milk, effects in breastfed infants, and the drugs it would consider insteadNo information is available on the use of leflunomide during breastfeeding, so an alternate drug is preferred, especially while nursing a newborn or preterm infant
National Institute of Child Health and Human Development, record revised April 15, 2023. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about leflunomide
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 66,185 reports naming leflunomide, and the FDA flagged 85% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- rheumatoid arthritis17,017 reports
- arthralgia12,089 reports
- joint swelling12,037 reports
- drug intolerance11,900 reports
- fatigue10,858 reports
- rash10,327 reports
- synovitis8,699 reports
- contraindicated product administered8,187 reports
Read these as a signal, not a rate. A report does not mean leflunomide caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
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Frequently asked questions
What is leflunomide?
Arava (Leflunomide) is an antirheumatic agent used to treat Rheumatoid Arthritis.
What kind of drug is leflunomide?
The FDA classifies leflunomide as an antirheumatic agent. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take leflunomide with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run leflunomide against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does leflunomide come in?
Across the brands we track, leflunomide is currently marketed as tablet, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic leflunomide?
We do not currently list a generic-labelled leflunomide product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Leflunomide: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/leflunomide
- MLA
- “Leflunomide: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/leflunomide.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for leflunomide on DailyMed (NIH) ↗ — including its boxed warning in full.