ENLARGEThe Ache: Oral nonsteroidal anti-inflammatory drugs, or NSAIDs, are widely used to reduce pain and swelling from arthritis and sprains and strains, but they can raise the risk for ulcers, heart attacks and stroke.
The Claim: Gels, patches and other topical NSAIDs can be used directly on the painful area, providing relief with very low levels of the medication entering the bloodstream, say companies that sell the products.
The Verdict: Topical anti-inflammatory medications show similar efficacy to oral drugs in clinical trials, and studies show comparatively small amounts of the medication gets into the bloodstream. Some scientists say it is logical that a lower exposure will result in lower risk, but so far a safety benefit hasn’t been proven.
The topical medications, available only by prescription in the U.S., contain an anti-inflammatory drug called diclofenac. Topical medications work the same way as oral drugs, by inhibiting enzymes involved in pain and inflammation. But they go directly through skin and underlying tissue to the problem area, instead of first traveling through the bloodstream, says Jeff Sherman, chief medical officer of Horizon Pharma PLC of Dublin.
ENLARGEHorizon’s Pennsaid 2%, a solution with the consistency of hand sanitizer, used twice a day for arthritis pain, hit the U.S. market last year. Other products include Voltaren Gel, sold byEndo Pharmaceuticals Inc., of Malvern, Pa., a four-times-daily treatment for knee arthritis; and Flector Patch, sold by Pfizer Inc. and applied twice a day for sprains and strains. Insurers generally cover all three products, but prior authorization may be required, physicians say. Topical NSAIDs are popular in Europe and world-wide, sold over-the-counter in many countries.
Based on the data, the topical products “can work as effectively” for pain relief as oral medications, says David Jevsevar, acting chairman of orthopedics at Dartmouth-Hitchcock Medical Center in Lebanon, N.H., and chairman of an expert panel that developed the 2012 American Academy of Orthopaedic Surgeons guidelines on knee arthritis, which suggest topicals as an option.
The medications are best used on superficial joints—such as the knee and elbow—and are less likely to be effective for deeper joints, such as the hip, he adds.
ENLARGEIn a 2012 review of 34 studies involving 7,688 participants, the Cochrane Collaboration, an independent scientific group, found topicals “equivalent” to oral medications for knee and hand arthritis. Another Cochrane review earlier this year also concluded that topicals provide good pain relief for sprains and strains. Side effects can include skin dryness and irritation, according to the scientific studies.
The three U.S. products haven’t been tested against each other in published clinical trials, so “there’s no way of predicting which one will work best for the individual patient,” says Marc C. Hochberg, a professor at the University of Maryland School of Medicine in Baltimore and head of the division of rheumatology and clinical immunology.
The topical medications in the U.S. carry the same boxed warning required by the Food and Drug Administration as oral NSAIDs, cautioning of a higher risk of serious cardiovascular and gastrointestinal problems.
ENLARGEThis warning is necessary because the medications haven’t been shown in large, rigorous “outcome studies” to be safer than oral medications, says Dr. Hochberg, who has worked as a paid consultant on Voltaren.
Despite the lack of large studies, some physicians think topicals are likely safer because less of the medication reaches the bloodstream. For example, in a 2008 study of Flector Patch, blood concentrations of diclofenac after four days of twice-a-day use was less than 1% of that seen with a comparable amount of oral medication. The study, published in the Journal of Pain, was funded by a company that formerly marketed the patch.
Other experts remain cautious given the lack of data. “We don’t know if there is a decrease in gastrointestinal toxicity or cardiovascular toxicity, because it’s a topical,” says Lee S. Simon, a former FDA director of analgesic, anti-inflammatory and ophthalmologic drug products. Dr. Simon—a principal at SDG LLC, a Cambridge, Mass., drug-development consulting firm that works with Horizon and other companies—added: “There are plenty of people who think it’s obvious, but I don’t.”
[“source-wsj”]