Agents currently approved by the FDA for use in OA and other painful conditions include diclofenac sodium 1% gel, diclofenac sodium topical solution 1.5% w/w in 45.5% dimethyl sulfoxide, and diclofenac epolamine 1.3%.⁷

“We found the clinical effect of the available topical NSAIDs to be very similar, despite some heterogeneity in their bioavailability. Thus, all topical NSAIDs should have similar efficacy for controlling knee or hand OA pain, and no one agent can currently be recommended over another,” Dr. Gambert said.

A Safer Option?

As with other NSAIDs, the prescribing information for topical agents includes boxed warnings regarding the risks for cardiovascular and gastrointestinal adverse events. Current data demonstrating low toxicity has called the necessity for such labeling into question, prompting the possibility of an amendment.⁶

Still, as with any drug, topical NSAIDs must be used with caution. “While severe gastrointestinal bleeding is reportedly less commonly with topical NSAIDS than with oral NSAIDS, it can occur. Also, these agents are not without other risks — more than 39% of [patients] report local adverse events, such as dry skin, erythema, pruritus, and even paresthesia,” Dr. Gambert pointed out.

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“Topical NSAIDs are best used when directed at a specific joint in the hand or when there is knee pain. They should not be used when multiple joints are involved, because systemic absorption can occur — the more that is used, the higher the blood levels and the greater the potential for adverse events,” Dr. Gambert advised.

Potential drug interactions must also be considered. Systemic absorption of topical NSAIDs can potentiate the action of warfarin, a drug commonly used by older adults, Dr. Gambert added.

Although current data indicate that topical NSAIDs provide a safer and non-inferior method of pain control for knee and hand OA than oral NSAIDs, Dr. Rannou noted that he would be interested in seeing more long-term studies on the topic.

“Because topical NSAIDs are used for years, it would be useful to have more information about their long-term safety and efficacy. Currently, it is unclear what effects the chronic use of these agents has on patients, and whether patients really should be using these agents long-term,” Dr. Rannou concluded.

References

1. Rannou F, Pelletier JP, Martel-Pelletier J. Efficacy and safety of topical NSAIDs in the management of osteoarthritis: evidence from real-life setting trials and surveys. Semin Arthritis Rheum. doi: doi:10.1016/j.semarthrit.2015.11.007.

2. Centers for Disease Control and Prevention. Osteoarthritis (OA). http://www.cdc.gov/arthritis/basics/osteoarthritis.htm. Updated October 28, 2015. Accessed December 11, 2015.

3. Buckwalter JA, Saltzman C, Brown T. The impact of osteoarthritis: implications for research. Clin Orthop Relat Res. 2004 Oct;(427 Suppl):S6-15. Review.

4. Bhatia D, Bejarano T, Novo M. Current interventions in the management of knee osteoarthritis. J Pharm Bioallied Sci. 2013 Jan;5(1):30-8. doi: 10.4103/0975-7406.106561.

5. US Food and Drug Administration. FDA Strengthens Warning of Heart Attack and Stroke Risk for Non-Steroidal Anti-Inflammatory Drugs. Published July 9, 2015. Accessed December 11, 2015.

6. Balmaceda CM. Evolving guidelines in the use of topical nonsteroidal anti-inflammatory drugs in the treatment of osteoarthritis. BMC Musculoskelet Disord. 2014 Jan 21;15:27. doi: 10.1186/1471-2474-15-27. Review.

7. McPherson ML, Cimino NM. Topical NSAID formulations. Pain Med. 2013 Dec;14 Suppl 1:S35-9. doi: 10.1111/pme.12288.