Sulfasalazine is an easy to use and well-tolerated medication. Some studies have shown it to be as effective as methotrexate as a DMARD. It is used more frequently in Europe than in the U.S.
Leflunomide (Arava) has been available for a number of years. It is known to inhibit pyrimidine synthesis and thereby alter T-cell function. Studies show it to be about as effective as methotrexate. It must be monitored as closely as methotrexate since its toxicities are remarkably similar. The rate of diarrhea and hair loss may be a bit higher with leflunomide, but it does not have the risk of pulmonary reaction.
Reference: Harris ED, Budd RC, Firestein GS, et al (eds): Kelley’s Textbook of Rheumatology, 7th ed. Philadelphia, W.B. Saunders, 2005