Physicians commonly encounter patients suffering from musculoskeletal disorders such as osteoarthritis and systemic non-steroidal anti-inflammatory drugs (NSAIDs) are frequently used to treat the resulting pain. While useful for treating chronic musculoskeletal pain systemic NSAIDs also have many undesirable side effects, such as gastrointestinal bleeding, which lead to consideration of alternative therapies. One therapy physicians may consider is topical NSAIDs in the form of creams, gels, patches, or solutions. Two questions naturally arise: are topical NSAIDs as effective as systemic NSAIDs in treating chronic musculoskeletal pain? Furthermore, are topical NSAIDs safer than their systemic counterparts in regards to undesirable adverse effects?
A Cochrane systematic review conducted in 2012 searched the Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE, as well as bibliographies of selected articles. In addition, electronic searches of companies known to be actively researching topical NSAIDs and clinical trial registers of topical NSAIDs were included. The selection criteria required that the trials be randomized, double blind studies with placebos or active comparators where at least one treatment was a topical NSAID of some form (cream, gel, patch, solution). Each treatment arm included at least 10 participants and the studies ran for no less than 2 weeks. The majority of the studies included male and female participants with a diagnosis of osteoarthritis of the knee or hand. Three of the studies looked at vaguely described disease processes including musculoskeletal pain of at least 3 months duration, soft tissue rheumatism, and cervical and lumbar back pain. In total, information was available from 7,688 participants from 32 studies, 23 of which compared topical NSAIDs to placebo. Each study’s validity was assessed and two review authors then extracted data.
The results showed that topical NSAIDs were significantly more effective than placebo for treating chronic musculoskeletal pain. Topical NSAIDs were associated with increased clinical success at 2-3 weeks in analysis of 7 trials with 917 adults (risk ratio [RR] 1.94, 95% CI 1.57-2.41, NNT 4-10). Topical NSAIDs included felbinac, piroxicam, ibuprofen, and diclofenac; piroxicam was the only one not better than placebo. The use of topical diclofenac in the treatment of osteoarthritis led to a 50% reduction in pain over 8 to 12 weeks when compared with placebo (NNT of 6.4 for the solution, 11 for the gel formulation). Comparison of topical NSAIDs to oral NSAIDs did not show any difference in efficacy. However, there were more local adverse events (such as skin irritation) with topical NSAIDs (RR 3.74, 95% CI 2.76-5.06, NNH 4-9) but gastrointestinal adverse events (like GI bleeding) were reduced (RR 0.66, 95% CI 0.56-0.77, NNH 8-16).
Currently the cost of topical NSAIDs and lack of insurance coverage are possible barriers that must be overcome for more healthcare providers to prescribe topical NSAIDs. Given the current evidence physicians should consider the use of topical NSAIDs for conditions such as osteoarthritis, especially in patients who have a predilection for gastrointestinal bleeding.
For more information, see the Topical NSAIDs topic in DynaMed.