OBJECTIVES: To compare the prescribing trends of traditional and COX-2 selective NSAIDs by different physician specialties. We also contrasted the appropriateness of NSAID medication use between physician specialties by comparing prescribing data to a clinically accepted therapeutic guideline on the appropriate use of these medications. METHODS: We conducted a retrospective cohort study using pharmacy claims and clinical data on 43,936 adult patients enrolled with an IPA of a midwestern University-associated managed care plan. We identified continuously enrolled managed care members who filled a new prescription for NSAID or NSAID combination from 1999-2002 on a chronic-use basis. RESULTS: In total, 1576 patients were started on a traditional NSAID or a COX-2 inhibitor. Primary care patients were younger and less likely to have comorbid conditions. Overall, COX-2 use was two times greater among patients seen by specialists compared to patients seen by PCPs. Use and appropriateness patterns between the specialties were similar over the time course of the analysis. Multivariate logistic regression showed that history of rheumatoid arthritis, osteoarthritis, generalized musculoskeletal pain, or a serious gastrointestinal complication were associated with increased likelihood of being prescribed a COX-2 inhibitor and being placed on therapy considered inappropriate. History of coronary artery disease and patient age were associated with an increased risk of receiving inappropriate therapy. CONCLUSION: In addition to prescribing COX-2 inhibitors at twice the rate of PCPs, specialists were less compliant with appropriate use guidelines that considered comorbidities. Overall compliance with appropriate use guidelines was 62%, with PCPs 67% and specialists 49%. Using this drug class as a model for physician adoption of new therapeutic agents, specialists were observed to be more likely to use new drugs, despite the lack of clinical scenarios supporting their use over traditional therapies. Education and interventions to promote appropriate prescribing should target both PCPs and specialists.