Lidocaine patches offer a common topical solution for localized pain relief. These patches deliver medication directly through the skin, aiming to alleviate pain without affecting the entire body. Their primary purpose is to offer targeted relief for various types of localized pain.
Understanding Lidocaine Patch Strengths
Over-the-counter (OTC) lidocaine patches typically contain 4% lidocaine, representing the maximum strength available without a prescription. These patches are widely accessible for managing minor aches and pains in areas like shoulders, arms, neck, and legs.
In contrast, prescription-strength lidocaine patches commonly contain 5% lidocaine. The 5% patch, often known by brand names like Lidoderm, is generally considered the strongest available and requires a doctor’s prescription. This higher concentration is typically prescribed for more specific conditions, such as post-herpetic neuralgia, a type of nerve pain following a shingles infection. Its increased concentration and intended use for more severe or persistent pain necessitate medical supervision.
How Lidocaine Patches Work
Lidocaine patches deliver lidocaine, a local anesthetic, directly to the affected area. Once applied to the skin, lidocaine blocks nerve signals in that localized region. This action inhibits the flow of sodium ions into nerve cells, preventing the initiation and transmission of pain impulses to the brain.
The patch provides targeted relief by interfering with the pain signals at their source in the peripheral nervous system. This localized effect reduces the sensation of pain without causing widespread numbness or affecting the entire body. Less than 5% of the lidocaine is absorbed systemically, which helps minimize the risk of broader effects.
Proper Application and Usage
Applying a lidocaine patch correctly is important for effectiveness and safety. Clean and dry the skin in the affected area, ensuring it is intact. Avoid applying the patch to broken or damaged skin, as this can increase the absorption of lidocaine into the bloodstream. If a smaller patch is needed, prescription patches can be cut with scissors before removing the protective liner.
The duration of wear varies by patch strength. Prescription 5% lidocaine patches are worn for no more than 12 hours within a 24-hour period, followed by a 12-hour patch-free interval. Over-the-counter 4% patches are applied for up to 8 hours, up to three or four times daily. It is important to remove the old patch before applying a new one. Avoid exposing the patch to direct heat sources like heating pads or electric blankets, as this can increase medication absorption.
When to Seek Medical Advice
While lidocaine patches are generally well-tolerated, consult a healthcare professional in certain situations. If pain persists, worsens, or does not improve after consistent use, seek medical evaluation. If skin irritation, redness, burning, or a rash develops at the application site and does not subside after removing the patch, seek advice.
Although uncommon with patches, symptoms suggesting systemic absorption, such as dizziness, confusion, blurred vision, or ringing in the ears, warrant immediate medical attention. Discuss any existing medical conditions, such as heart, lung, or liver disease, or other medications that could interact with lidocaine.