Recommendations for the Use of Methotrexate in Juvenile Idiopathic Arthritis

Abstract

Juvenile idiopathic arthritis (JIA) is one of the most common rheumatic diseases in childhood. In a significant number of JIA cases the disease is resistant to therapy with NSAIDs, intra-articular corticosteroid injections, and physiotherapy, and methotrexate is used as a second-line agent. The efficacy of methotrexate therapy in children with JIA has been demonstrated in prospective controlled trials and this agent appears to have slightly superior efficacy compared with leflunomide. Data from randomized studies indicate a starting dose of 10-15 mg/m(2)/week orally. The dose of parenteral methotrexate can be increased to 15-20 mg/m(2)/week. Combination therapy with methotrexate and an NSAID is recommended. However, there are still no data on when to initiate methotrexate in JIA and how long children should be treated. The most common adverse effects are aversion to the drug and nausea. In the case of minor adverse effects the use of folic acid at a dosage of 1 mg/day is feasible. In JIA, daily folate supplementation has only been studied in one small heterogeneous cohort with a very short observation period and, at present, a general recommendation on daily folate supplementation cannot be made. In summary, methotrexate is seen by many pediatric rheumatologists as the first-choice, second-line drug; there is good evidence of its efficacy in JIA. However, in light of the recent introduction of biologic agents, the place of methotrexate in the treatment of JIA may have to be redefined in the coming years.