title: 5-Aminosalicylic acid or sulphapyridine. Which is the active moiety of sulphasalazine in rheumatoid arthritis?
abstract: Thirty patients with active rheumatoid arthritis participated in an open study of 6 months' treatment with either 5-aminosalicylic acid or sulphapyridine, the two moieties of sulphasalazine. Patients were assessed at regular intervals using a number of clinical and biochemical tests designed to detect specific antirheumatic activity. Patients taking sulphasalazine showed significant improvement in most parameters of disease activity, but those taking 5-aminosalicylic acid did not improve despite the fact that high serum concentrations of 5-aminosalicylic acid and acetyl 5-aminosalicylic acid were achieved. These results suggest that sulphapyridine is the active moiety of sulphasalazine. Its possible mode of action is discussed. Nausea was a frequent problem in patients taking sulphapyridine. Unless this problem can be overcome, sulphapyridine is unlikely to offer any therapeutic advantages over sulphasalazine in the treatment of rheumatoid arthritis.
mesh_terms: D000328:Adult; D000368:Aged; D000636:Aminosalicylic Acids / Q000627:therapeutic use*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D019804:Mesalamine; D008875:Middle Aged; D013424:Sulfanilamides / Q000627:therapeutic use*; D013427:Sulfapyridine / Q000627:therapeutic use*; D012460:Sulfasalazine / Q000627:therapeutic use*
chemical_list: D000636:Aminosalicylic Acids; D000894:Anti-Inflammatory Agents, Non-Steroidal; D013424:Sulfanilamides; D012460:Sulfasalazine; D019804:Mesalamine; D013427:Sulfapyridine