The four commonly used DMARDs namely methotrexate (MTX), hydroxychloroquine (HCQ), leflunomide (LEF), and sulfasalazine (SSZ) have far superior therapeutic and toxicity ratio than rest of the drugs. There is substantial clinical experience and evidence with regard to the use of these drugs. MTX is a well-studied DMARD with greater clinical evidence. MTX, at a dose ranging from 7.5 mg to 25 mg per week, is indicated for relieving pain, reducing the number of affected joints, and to gain functional improvement (Prescrire Int. 2010). However, in Japan the hepatotoxicity due to MTX is reported to be higher, despite the use of the drug in smaller doses. HCQ is still not approved as a DMARD in Japan. Tacrolimus and bucillamine, a derivative of D-penicillamine, are used more frequently in Japan and Korea than any other countries. Both the drugs are approved as DMARDs in these two countries (Matsuno H, 2013). In India and a few of the Western countries; drugs like mycophenolate mofetil, cyclophosphamide, cyclosporine are used for treating specific indications like ILD and vasculitis, and in patients who cannot use either MTX or biologics. AZA, cyclosporine, and gold salts were used more commonly during pre-MTX era. 

REFERENCES

1. Rheumatoid arthritis: choice of antirheumatic Methotrexate first. Prescrire Int. 2010;19(105):30-4.
2. Matsuno H: Small molecule DMARD theraphy and its position in RA Innovative rheumatology (Intech, Croatia), Matsuno H.eds.,165- 187,2013.