Lidocaine patches deliver medication directly through the skin for targeted pain relief. They contain lidocaine, a local anesthetic that blocks pain signals from reaching the brain by numbing the affected area.
Can You Apply Lidocaine Patches to the Bottom of Your Feet?
Applying lidocaine patches to the bottom of the feet is generally considered acceptable for various localized pain conditions. Many individuals use them for common foot ailments such as plantar fasciitis, metatarsalgia, general soreness, or peripheral neuropathy. The medication, lidocaine, functions by inhibiting the flow of sodium ions into nerve cells, preventing them from transmitting pain signals.
While the skin on the soles of the feet is thicker than other areas, lidocaine can still penetrate sufficiently to produce an analgesic effect. The amount of lidocaine absorbed systemically from these patches is minimal, typically less than 5%, which helps to reduce the risk of widespread effects. Both over-the-counter 4% lidocaine patches and prescription 5% lidocaine patches are available. It is important to apply these patches only to intact skin, avoiding any broken, irritated, or infected areas.
Specific Considerations for Foot Application
When applying lidocaine patches to the soles of the feet, several factors should be considered due to the distinct characteristics of this area. The skin on the soles is thicker, which means drug absorption might be slower compared to thinner skin areas. Proper placement is important to prevent the patch from dislodging or causing irritation from the constant pressure and friction of shoes and walking.
Sweat and moisture can affect the patch’s adhesion and potentially lead to skin irritation. Therefore, ensure the foot area is clean and thoroughly dry before application to promote proper adherence. After cleaning, press the patch firmly onto the skin. Patches can be cut to fit the specific painful area. Most patches are designed for up to 12 hours of wear within a 24-hour period, followed by a 12-hour patch-free interval, with OTC versions typically worn 8 to 12 hours.
Understanding Potential Side Effects and When to Seek Advice
While lidocaine patches are generally well-tolerated, some individuals may experience localized skin reactions at the application site. These can include redness, itching, rash, a burning sensation, or even blistering, bruising, and swelling. Such reactions are typically mild and temporary, often resolving within minutes to hours after the patch is removed.
Applying patches to large areas, broken skin, or for longer than recommended durations can increase the risk of systemic absorption. Signs of systemic toxicity include dizziness, confusion, drowsiness, nausea, vomiting, blurred vision, or ringing in the ears. A serious blood disorder, methemoglobinemia, has also been reported.
Lidocaine patches should not be used by individuals with a known allergy to lidocaine. Do not apply heat sources like heating pads over the patch, as this can increase drug absorption. If severe skin reactions occur, pain worsens or does not improve, or any signs of systemic absorption manifest, consult a healthcare professional. Individuals with underlying health conditions, such as liver or heart issues, should also seek medical advice before use.