Topical nonsteroidal anti-inflammatory drugs for osteoarthritis

Nonsteroidal anti-inflammatory drugs (NSAIDs) are mainstays of the treatment of osteoarthritis (OA) but have dose- and age-related risks of gastrointestinal, cardiovascular, and renal adverse events (AEs). As a result, US and international guidelines recommend caution when prescribing oral NSAIDs, particularly in older patients and those with significant comorbidities. For OA of the hands and knees, topical NSAIDs provide efficacy similar to oral NSAIDs, with far less systemic distribution. Treatment-related cardiovascular, renal, and other serious AEs with topical NSAIDs have not been reported. At present, only 2 topical NSAIDs are approved in the United States for the treatment of OA: diclofenac sodium 1% gel for hand or knee OA and diclofenac sodium 1.5% in 45.5% dimethylsulfoxide solution for knee OA. Clinical trial data for these products have demonstrated efficacy superior to placebo or similar to oral diclofenac with AE profiles similar to placebo, except for application site reactions. In large double-blind trials, gastrointestinal AEs were infrequent and did not include ulcers, perforations, or bleeding. The purpose of this brief review is to examine the data from controlled double-blind trials evaluating the use of topical NSAIDs in patients with OA. Articles included were identified via a search of PubMed covering the period from January 1, 2005 through March 31, 2010. Reference lists from OA treatment guidelines and meta-analyses were reviewed for additional citations of importance.