Combination therapy of rheumatoid arthritis--rationale and overview.

Currently available therapeutic agents for the treatment of rheumatoid arthritis are unsatisfactory for many patients, due either to inefficacy, loss of effectiveness with time, or toxicity. One approach is to study drugs in combination, at lower than usual dosages of each, in order to achieve greater efficacy with fewer adverse reactions. To aid in this review of published trials, the various combinations have been arbitrarily divided into combinations of cytotoxic (antiproliferative) drugs with each other, and combinations of noncytotoxic drugs. Of the noncytotoxic combinations, intramuscular gold with D-penicillamine appeared to offer the best results without increased side effects when compared to each one used alone. The most promising cytotoxic combination was methotrexate with azathioprine.