Methotrexate and sulphasalazine as combination therapy in rheumatoid arthritis.

Sulphasalazine (SASP) and methotrexate (MTX) are well-established treatments for RA but the use of these drugs in combination has been avoided as both have antifolate activity. In this paper we report our experience with 32 patients treated with the combination MTX/SASP and compare the toxicity and tolerability of the combination with 63 patients treated with MTX alone. The median duration of exposure to the combination was 23 months. Nineteen patients have continued this regime for over 18 months. Five patients on MTX/SASP combination discontinued MTX, in four cases due to toxicity and in one because MTX/SASP was ineffective. In 17 patients on MTX alone, the drug was withdrawn permanently. In seven cases the cause was toxicity including two patients with severe reactions. In patients known to tolerate SASP alone, the combination of MTX/SASP is also well tolerated. In our experience of 48 patient-years of such combination therapy, there is no increase in toxicity compared to therapy with MTX alone in RA.