Flector Patch is a prescription adhesive patch that delivers a pain-relieving anti-inflammatory drug directly through the skin. It contains 1.3% diclofenac epolamine, a nonsteroidal anti-inflammatory drug (NSAID), and is FDA-approved for treating acute pain from minor strains, sprains, and bruises.
How the Flector Patch Works
The patch releases diclofenac steadily into the skin at the site where you apply it. Diclofenac reduces pain and inflammation by blocking the production of prostaglandins, chemicals your body makes in response to injury that trigger swelling, pain, and tenderness. By delivering the drug locally rather than through your digestive system, the patch targets the injured area more directly than a pill would.
The systemic absorption is remarkably low. After four days of repeated use, the amount of diclofenac that reaches your bloodstream is less than 1% of what you’d absorb from a single 50-mg oral diclofenac tablet. This is the patch’s main advantage: it provides anti-inflammatory relief at the injury site while keeping whole-body drug exposure minimal.
What the Patch Treats
Flector Patch is specifically approved for acute, short-term pain from soft tissue injuries. That means it’s designed for things like a twisted ankle, a pulled muscle, or a bruise from a fall. It is not intended for chronic joint conditions like arthritis, surgical pain, or deep injuries. If you’ve been prescribed it, it’s typically for an injury that happened recently and is expected to heal on its own with time.
How to Apply It
The standard dose is one patch applied to the most painful area twice a day. You apply the patch directly over the injury on clean, intact skin. Don’t place it on broken skin, open wounds, or areas with a rash. The general guidance is to use the lowest effective dose for the shortest time needed, so your prescriber will likely recommend a limited course rather than ongoing use.
Each patch stays on for roughly 12 hours before you replace it with a fresh one. If the edges start to peel, mesh medical tape can help hold it in place. Avoid wrapping the area tightly with bandages or applying heat over the patch, as this could change how much drug is absorbed.
Side Effects
The most common side effects are skin reactions at the application site. In clinical trials involving 572 patients, about 11% experienced some type of local skin issue. The breakdown looked like this:
- Itching: 5% of patients
- Skin irritation or dermatitis: 2%
- Other reactions (dryness, redness, discoloration, small blisters): 4%
Interestingly, patients using a placebo patch (no medication) had similar rates of skin reactions, at 12%. This suggests that much of the irritation comes from wearing an adhesive patch on the skin rather than from the drug itself. Most of these reactions are mild and resolve once you stop using the patch.
Risks Shared With Other NSAIDs
Even though very little diclofenac enters your bloodstream from the patch, it still carries the standard warnings that apply to all NSAIDs. These include a potential for cardiovascular problems (heart attack, stroke) and gastrointestinal issues (stomach bleeding, ulcers), particularly with long-term use or in people who already have risk factors for those conditions. The FDA requires these warnings on all NSAID products regardless of how they’re delivered.
You should not use the Flector Patch if you’ve had an allergic reaction to aspirin or other NSAIDs, including symptoms like hives, facial swelling, or asthma attacks triggered by pain relievers. It’s also not appropriate right before or after heart surgery.
Flector Patch vs. Oral Pain Relievers
The primary appeal of the patch is targeted delivery with minimal systemic exposure. When you take an NSAID pill, the drug circulates through your entire body, which is why oral NSAIDs can cause stomach irritation, kidney strain, and cardiovascular stress over time. The Flector Patch sidesteps most of that by concentrating the drug at the injury. Less than 1% of the drug reaches your bloodstream compared to an oral dose, which substantially lowers the risk of those whole-body side effects.
The tradeoff is that the patch only works for superficial soft tissue injuries where the drug can penetrate through the skin to the affected area. For deeper pain, widespread inflammation, or conditions affecting joints with thick tissue coverage, an oral medication or a different treatment approach is typically more effective. The patch also requires a prescription, while many oral NSAIDs like ibuprofen are available over the counter.