Liver toxicity is rare in rheumatoid arthritis patients using combination therapy with leflunomide and methotrexate.

Objective: Some studies have reported that adding leflunomide (LEF) to the treatment of rheumatoid arthritis (RA) in patients who do not respond to methotrexate (MTX) improved efficacy but increased the risk of liver toxicity. This study aimed at assessing the incidence of liver toxicity in patients with active RA using the LEF and MTX combination therapy in comparison with that of patients on MTX monotherapy.

Methods: Between February and September 2009, 97 consecutive patients followed up at the University Hospital of the Universidade Federal de Santa Catarina, Brazil, were enrolled.