Haagsma, C J Influence of sulphasalazine, methotrexate, and the combination of both on plasma homocysteine concentrations in patients with rheumatoid arthritis. [electronic resource] - Annals of the rheumatic diseases Feb 1999 - 79-84 p. digital Publication Type: Clinical Trial; Comparative Study; Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't ISSN: 0003-4967 Standard No.: 10.1136/ard.58.2.79 doi Subjects--Topical Terms: Antirheumatic Agents--adverse effectsArthritis, Rheumatoid--bloodDigestive System--drug effectsDouble-Blind MethodDrug Therapy, CombinationFemaleFolic Acid--bloodHomocysteine--bloodHumansMaleMethotrexate--adverse effectsMethylenetetrahydrofolate Reductase (NADPH2)Middle AgedMutationOxidoreductases Acting on CH-NH Group Donors--geneticsSulfasalazine--adverse effectsVitamin B 12--blood