AdultPediatricDosage Forms & Strengths tablet 10mg 20mg 100mg Rheumatoid Arthritis 100 mg PO qDay for 3 day initially, THEN 10-20 mg PO qDay Dosage Modifications Renal impairment No dosage adjustment provided by the manufacturer; use with caution Hepatic Impairment Preexisting liver disease: Not recommended Baseline ALT >2 times ULN: Not recommended Severe hepatic impairment: Contraindicated Hepatotoxicity following administration: Discontinue therapy and determine cause; if lefluonamide induced, discontinue treatment and initiate accelerated drug elimination process Dosing Considerations Discontinuing leflunomide Drug elimination process recommended to achieve nondetectable plasma levels (ie, <0.02 mg/L) after discontinuation Step 1: Administer cholestyramine 8 g PO TID 11 days; the 11 days do not need to be consecutive unless there is a need to lower the plasma level rapidly Step 2: Verify plasma levels <0.02 mg/L by 2 separate tests at least 14 days apart; if plasma levels >0.02 mg/L, consider additional cholestyramine treatment Without the drug elimination procedure, it may take up to 2 years to reach plasma M1 metabolite levels <0.02 mg/L due to individual variation in drug clearance Safety and efficacy not establishedInteraction CheckerEnter a drug name and leflunomideNo Results No Interactions Found Interactions FoundContraindicatedSerious - Use AlternativeSignificant - Monitor CloselyMinorAll Interactions Sort By: SeverityName Contraindicated (0)Serious - Use Alternative (74)adalimumabadalimumab and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.alefaceptalefacept and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.anakinraanakinra and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.anthrax vaccineleflunomide decreases effects of anthrax vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.antithymocyte globulin equineantithymocyte globulin equine and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.antithymocyte globulin rabbitantithymocyte globulin rabbit and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.axicabtagene ciloleucelleflunomide, axicabtagene ciloleucel. Either increases effects of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.azathioprineazathioprine and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.basiliximabbasiliximab and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.BCG vaccine liveleflunomide decreases effects of BCG vaccine live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.beclomethasone, inhaledbeclomethasone, inhaled increases toxicity of leflunomide by unspecified interaction mechanism. Avoid or Use Alternate Drug. May increase risk of hematologic toxicities; should monitor for bone marrow suppression at least monthly throughout duration of concurrent therapy when leflunomide is given with another immunosuppressants.brexucabtagene autoleucelleflunomide, brexucabtagene autoleucel. Either increases effects of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.canakinumabcanakinumab and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.ciltacabtagene autoleucelleflunomide, ciltacabtagene autoleucel. Either increases effects of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.cyclosporinecyclosporine and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.darolutamidedarolutamide will increase the level or effect of leflunomide by Other (see comment). Avoid or Use Alternate Drug. Darolutamide is a BCRP inhibitor. Avoid coadministration with BCRP inhibitors. If use is unavoidable, closely monitor for adverse reactions and consider dose reduction of BCRP substrate drug (refer BCRP substrate prescribing information).diphtheria & tetanus toxoidsleflunomide decreases effects of diphtheria & tetanus toxoids by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.diphtheria & tetanus toxoids/ acellular pertussis vaccineleflunomide decreases effects of diphtheria & tetanus toxoids/ acellular pertussis vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.diphtheria & tetanus toxoids/acellular pertussis/poliovirus, inactivated vaccineleflunomide decreases effects of diphtheria & tetanus toxoids/acellular pertussis/poliovirus, inactivated vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.etanerceptetanercept and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.everolimuseverolimus and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.glatiramerglatiramer and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.golimumabgolimumab and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.hepatitis A vaccine inactivatedleflunomide decreases effects of hepatitis A vaccine inactivated by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.hepatitis a/b vaccineleflunomide decreases effects of hepatitis a/b vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.hepatitis a/typhoid vaccineleflunomide decreases effects of hepatitis a/typhoid vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.hepatitis b vaccineleflunomide decreases effects of hepatitis b vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.human papillomavirus vaccine, nonavalentleflunomide decreases effects of human papillomavirus vaccine, nonavalent by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Immunosuppressive therapies, including irradiation, antimetabolites, alkylating agents, cytotoxic drugs, and corticosteroids (used in greater than physiologic doses), may reduce the immune responses to vaccines.human papillomavirus vaccine, quadrivalentleflunomide decreases effects of human papillomavirus vaccine, quadrivalent by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Immunosuppressive therapies, including irradiation, antimetabolites, alkylating agents, cytotoxic drugs, and corticosteroids (used in greater than physiologic doses), may reduce the immune responses to vaccines.hydroxychloroquine sulfatehydroxychloroquine sulfate and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.idecabtagene vicleucelleflunomide, idecabtagene vicleucel. Either increases effects of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.infliximabinfliximab and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.influenza virus vaccine quadrivalentleflunomide decreases effects of influenza virus vaccine quadrivalent by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.influenza virus vaccine quadrivalent, adjuvantedleflunomide decreases effects of influenza virus vaccine quadrivalent, adjuvanted by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Immunosuppressive drugs may reduce the immune response to influenza vaccine.influenza virus vaccine quadrivalent, cell-culturedleflunomide decreases effects of influenza virus vaccine quadrivalent, cell-cultured by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.influenza virus vaccine quadrivalent, intranasalleflunomide decreases effects of influenza virus vaccine quadrivalent, intranasal by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.influenza virus vaccine trivalentleflunomide decreases effects of influenza virus vaccine trivalent by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.influenza virus vaccine trivalent, adjuvantedleflunomide decreases effects of influenza virus vaccine trivalent, adjuvanted by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Immunosuppressive drugs may reduce the immune response to influenza vaccine.Japanese encephalitis virus vaccineleflunomide decreases effects of Japanese encephalitis virus vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.lasmiditanlasmiditan increases levels of leflunomide by Other (see comment). Avoid or Use Alternate Drug. Comment: Lasmiditan inhibits BCRP in vitro. Avoid coadministration of lasmiditan with BCRP substrates.leniolisibleniolisib will increase the level or effect of leflunomide by Other (see comment). Avoid or Use Alternate Drug. Leniolisib, a BCRP inhibitor, may increase systemic exposure of BCRP substrateslisocabtagene maraleucelleflunomide, lisocabtagene maraleucel. Either increases effects of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.measles (rubeola) vaccineleflunomide decreases effects of measles (rubeola) vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.measles mumps and rubella vaccine, liveleflunomide decreases effects of measles mumps and rubella vaccine, live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.measles, mumps, rubella and varicella vaccine, liveleflunomide decreases effects of measles, mumps, rubella and varicella vaccine, live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.meningococcal A C Y and W-135 polysaccharide vaccine combinedleflunomide decreases effects of meningococcal A C Y and W-135 polysaccharide vaccine combined by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.muromonab CD3leflunomide and muromonab CD3 both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.mycophenolateleflunomide and mycophenolate both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.pneumococcal vaccine 13-valentleflunomide decreases effects of pneumococcal vaccine 13-valent by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.pneumococcal vaccine heptavalentleflunomide decreases effects of pneumococcal vaccine heptavalent by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.pneumococcal vaccine polyvalentleflunomide decreases effects of pneumococcal vaccine polyvalent by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.rabies vaccineleflunomide decreases effects of rabies vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants may interfere with development of active immunity.rabies vaccine chick embryo cell derivedleflunomide decreases effects of rabies vaccine chick embryo cell derived by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.rilonaceptleflunomide and rilonacept both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.rotavirus oral vaccine, liveleflunomide decreases effects of rotavirus oral vaccine, live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.rubella vaccineleflunomide decreases effects of rubella vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.selinexorselinexor, leflunomide. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.sirolimusleflunomide and sirolimus both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.smallpox (vaccinia) vaccine, liveleflunomide decreases effects of smallpox (vaccinia) vaccine, live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.tacrolimusleflunomide and tacrolimus both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.temsirolimusleflunomide and temsirolimus both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.tetanus toxoid adsorbed or fluidleflunomide decreases effects of tetanus toxoid adsorbed or fluid by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.tick-borne encephalitis vaccineleflunomide decreases effects of tick-borne encephalitis vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.tisagenlecleucelleflunomide, tisagenlecleucel. Either increases effects of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.tocilizumabtocilizumab and leflunomide both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.tofacitinibleflunomide, tofacitinib. Either increases toxicity of the other by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.tongkat alileflunomide and tongkat ali both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.travelers diarrhea and cholera vaccine inactivatedleflunomide decreases effects of travelers diarrhea and cholera vaccine inactivated by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.typhoid polysaccharide vaccineleflunomide decreases effects of typhoid polysaccharide vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.typhoid vaccine liveleflunomide decreases effects of typhoid vaccine live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.ustekinumableflunomide and ustekinumab both increase immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug.varicella virus vaccine liveleflunomide decreases effects of varicella virus vaccine live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.yellow fever vaccineleflunomide decreases effects of yellow fever vaccine by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.zoster vaccine liveleflunomide decreases effects of zoster vaccine live by pharmacodynamic antagonism. Contraindicated. Immunosuppressants also increase risk of infection with concomitant live vaccines.Monitor Closely (62)acalabrutinibacalabrutinib increases levels of leflunomide by Other (see comment). Use Caution/Monitor. Comment: Acalabrutinib may increase exposure to coadministered BCRP substrates by inhibition of intestinal BCRP.apalutamideapalutamide will decrease the level or effect of leflunomide by increasing elimination. Use Caution/Monitor. Apalutamide weakly induces BCRP and may decrease systemic exposure of drugs that are BCRP substrates.astragalusleflunomide increases and astragalus decreases immunosuppressive effects; risk of infection. Effect of interaction is not clear, use caution. Use Caution/Monitor.belataceptbelatacept and leflunomide both increase immunosuppressive effects; risk of infection. Use Caution/Monitor.carvedilolleflunomide will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.cholera vaccineleflunomide decreases effects of cholera vaccine by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Immunosuppressive therapies, including irradiation, antimetabolites, alkylating agents, cytotoxic drugs and corticosteroids (used in greater than physiologic doses), may reduce the immune response to cholera vaccine.cholestyraminecholestyramine decreases levels of leflunomide by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.dengue vaccineleflunomide decreases effects of dengue vaccine by immunosuppressive effects; risk of infection. Use Caution/Monitor. Immunosuppressive therapies (eg, irradiation, antimetabolites, alkylating agents, cytotoxic drugs, corticosteroids [greater than physiologic doses]) may reduce immune response to dengue vaccine.denosumableflunomide, denosumab. Other (see comment). Use Caution/Monitor. Comment: Caution should be taken in patients on concomitant immunosuppressants or with impaired immune systems