Rationale: The recommendation attaches a relatively high value for avoiding adverse effects of oral NSAIDs. Resources: Topical NSAIDs are relatively cheap.
A Cochrane review included 39 studies with a total of 10 631 subjects. All studies examined topical NSAIDs for treatment of osteoarthritis, 33 studies compared a topical NSAID with carrier.
In studies lasting 6 to 12 weeks, topical diclofenac and topical ketoprofen were significantly more effective than carrier for reducing pain; about 60% of participants had much reduced pain. With topical diclofenac, the NNT for clinical success in six trials (2343 participants) was 9.8 (95% CI 7.1 to 16). With topical ketoprofen, the NNT for clinical success in four trials (2573 participants) was 6.9 (5.4 to 9.3). There was too little information for analysis of other individual topical NSAIDs compared with carrier. Few trials compared a topical NSAID to an oral NSAID, but overall they showed similar efficacy. These efficacy results were almost completely derived from people with knee osteoarthritis.
There was an increase in local adverse events (mostly mild skin reactions) with topical diclofenac compared with carrier or oral NSAIDs, but no increase with topical ketoprofen. Reporting of systemic adverse events (such as gastrointestinal upsets) was poor, but where reported there was no difference between topical NSAID and carrier. Clinical success with carrier occurred commonly - in around half the participants in studies lasting 6 to 12 weeks. Both direct and indirect comparison of clinical success with oral placebo indicates that response rates with carrier (topical placebo) are about twice those seen with oral placebo.
; 23 studies compared a topical non-steroidal anti-inflammatory drug (NSAID) with placebo. Participants were treated for at least 2 and for different durations up to 12 weeks (Table ). Topical NSAIDs were significantly more effective than placebo for reducing pain due to chronic musculoskeletal conditions (RR 1.95, 95% CI 1.57 to 2.41; 7 studies, n=917). The best data were for topical diclofenac in osteoarthritis, where the NNT for at least 50% pain relief over 8 to 12 weeks compared with placebo was 6.4 for the solution, and 11 for the gel formulation. There were too few data of good quality to calculate NNTs for other individual topical NSAIDs compared with placebo. Direct comparison of topical NSAID with an oral NSAID did not show any difference in clinical success (RR 1.02, 95% CI 0.94 to 1.11; 5 studies, n=1 734). There was an increase in local adverse events (mostly mild skin reactions) with topical NSAIDs compared with placebo (RR 1.69, 95% CI 1.45 to 1.98) or oral NSAIDs (RR 3.74, 95% CI 2.76 to 5.06; 5 studies, n=1 651), but no increase in serious adverse events. Gastrointestinal adverse events with topical NSAID did not differ from placebo (RR 1.13, 95% CI 0.80 to 1.58; 15 studies, n=3 647), but were less frequent than with oral NSAIDs (RR 0.66, 95% CI 0.56 to 0.77; 6 studies, n=1 961).| Treatment | Number of participants (studies) | Success with topical NSAID (%) | Success with placebo (%) | RR (95% CI) | NNT (95% CI) |
|---|---|---|---|---|---|
| All topical NSAIDs | |||||
| 2 to 3 weeks | 917 (7) | 37 | 19 | 1.9 (1.6 to 2.4) | 5.5 (4.2 to 8.1) |
| 4 to 6 weeks | 810 (5) | 42 | 24 | 1.7 (1.4 to 2.1) | 5.8 (4.2 to 9.1) |
| 8 to 12 weeks | 2 440 (4) | 60 | 50 | 1.2 (1.1 to 1.3) | 10 (7.3 to 17) |
| Topical diclofenac | |||||
| 2 to 3 weeks | 569 (4) | 40 | 20 | 2.0 (1.5 to 2.6) | 5.0 (3.6 to 7.8) |
| 4 to 6 weeks | 375 (2) | 48 | 28 | 1.7 (1.3 to 2.2) | 5.2 (3.5 to 11) |
| 8 to 12 weeks | 2 440 (4) | 60 | 50 | 1.2 (1.1 to 1.3) | 10 (7.3 to 17) |
Date of latest search: 2016-02-03