Arthritis Osteoarthritis Living With Using the Flector Diclofenac Patch for Knee Pain By Carol Eustice Updated on June 02, 2023 Medically reviewed by David Ozeri, MD Print Table of Contents View All Table of Contents What It Does Who It's For Who Shouldn't Use It Insurance Issues Side Effects Drug Interactions Bottom Line Many patients like to use skin patches for osteoarthritis knee pain. One such option is the Flector patch, which delivers a pain-relieving nonsteroidal anti-inflammatory drug (NSAID) to the sore knee for twelve hours at a time. Sasha_Suzi / Getty Images What It Does The Flector patch is a topical formulation available as a skin patch that contains 1.3% diclofenac epolamine, an NSAID. The patch, which measures approximately 4 inches by 5.5 inches, is an alternative to the oral formulation of diclofenac (Voltaren) and the topical gel formulation (Voltaren gel). The Flector patch was approved by the Food and Drug Administration in 2007, and it is marketed in the United States by Alpharma. It has been available in Switzerland since 1993 and is approved in over three dozen countries. Indications The Flector patch was approved to treat acute pain due to minor strains, sprains, and contusions. It is primarily recommended for and used by patients who cannot tolerate oral diclofenac. One Flector patch should be applied twice daily (every twelve hours). Studies have shown that topical diclofenac formulations (gels, patches, or plasters) are superior or equivalent to oral diclofenac formulations. A 2017 review of studies concluded that topical diclofenac is as effective for the treatment of osteoarthritis and musculoskeletal injuries as oral NSAIDs, with minimal side effects. The 2019 American College of Rheumatology/Arthritis Foundation guidelines for osteoarthritis treatment give topical NSAIDs like Flector a "strong" recommendation for knee arthritis and a "conditional" recommendation for hand and hip arthritis. They recommend using them prior to trying oral NSAIDs. Who Should Not Use the Flector Patch The Flector patch is not an appropriate treatment for everyone. The patch should not be used by: Patients allergic to diclofenac, aspirin, or other NSAIDsPatients who just had or will be having a coronary artery bypass graft The Flector patches have the same warnings that the pills do, with labels listing the cardiovascular and gastrointestinal risks common to NSAIDs. Using the patch and the oral medication at the same time may increase adverse effects associated with NSAIDs. You should not use any lotions or cosmetics on the same site that you are applying the Flector patch, not even sunscreen. They could affect absorption and reduce how well you tolerate the patch medication. Studies haven't yet established whether the patch is safe for effective for children. The testing didn't include enough subjects over age 65 to understand if it might have a different response in younger patients. Nonformulary Treatment Some insurance companies list diclofenac patches as "nonpreferred" and "nonformulary." The diclofenac patch is expensive compared to its oral counterpart. Insurance companies would prefer you use something less expensive but just as effective. Patients who cannot use the cheaper alternatives are appropriate candidates for the diclofenac patch. Possible Side Effects Signs of an allergic reaction—including hives and the swelling of the face, lips, tongue, and throat—require emergency assistance. Otherwise, the risk of serious side effects is low for the diclofenac patch. The drug label says to stop using the patch and contact your healthcare provider right away if you experience these side effects: NauseaFatigue or weaknessItchingYellow eyes or skinStomach painFlu-like symptomsVomiting bloodBloody, black, or tarry stoolUnusual weight gainSkin rash or blisters with feverSwelling of the arms and legs, hands and feet Drug Interactions Certain drugs that you may already be taking can interact with the Flector (diclofenac) patch, such as Coumadin (warfarim), digoxin, pemetrexed, cyclosporine, lithium, methotrexate, diuretics, steroids, and ACE inhibitors. Bottom Line While the Flector patch is not for everyone, it may be an option for you. Consult with your healthcare provider and discuss all of your treatment options. 3 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Tieppo Francio V, Davani S, Towery C, Brown TL. Oral versus topical diclofenac sodium in the treatment of osteoarthritis. J Pain Palliat Care Pharmacother. 2017;31(2):113-120. doi:10.1080/15360288.2017.1301616 Kolasinski SL, Neogi T, Hochberg MC, et al. 2019 American College of Rheumatology/Arthritis Foundation guideline for the management of osteoarthritis of the hand, hip, and knee. Arthritis Care Res (Hoboken). 2020;72(2):149-162. doi:10.1002/acr.24131 U.S. National Library of Medicine. DailyMed. Flector patch drug label information. By Carol Eustice Carol Eustice is a writer who covers arthritis and chronic illness. She is the author of "The Everything Health Guide to Arthritis." See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit