The use of NSAIDs masked the diagnosis of gout in nine patients with the chronic polyarticular form of the disease. The escape from detection of chronic polyarticular gout resulted in a needless dependence on NSAIDs, failure to correct the metabolic problem, and in some cases progression of joint destruction. Although acute inflammation was modified, basic pathogenic mechanisms remained unchecked and joint disease continued. The indiscriminate use of NSAIDs may, by promoting misdiagnosis, become a major obstacle to effective control of this, perhaps the most remediable of arthritic disorders.