Topical analgesics are pain-relieving products that are applied directly to the skin. Some of these products contain natural ingredients, such as herbs and plants, and others contain medications to ease pain. Patients who have arthritis and other conditions that cause pain in the joints and muscles often benefit from these products, some of which are available over the counter.
The most common over-the-counter topical analgesics contain menthol or capsaicin as the active ingredient. Menthol in creams, lotions or pain-relieving gels works by stimulating the kappa opioid receptors in the brain that help with pain relief. It also brings a cooling sensation to the area, helping to relieve inflammation that leads to pain. Capsaicin, which is derived from hot peppers, is another natural substance often used in topical analgesics. These creams temporarily remove chemicals from the nerve cells that are responsible for sending pain messages to the brain.
Other pain-relieving creams rely on salicylates, the pain-relieving components of aspirin, to bring patients relief. These creams are also available over the counter and are particularly helpful for patients suffering from muscle pain. Natural pain relievers such as capsaicin often work better on patients who are suffering from nerve pain.
Products containing menthol or capsaicin are generally safe for almost anyone to use, though they should not be applied to broken or otherwise damaged skin. People who are allergic to or highly sensitive to hot peppers should not use products that contain capsaicin, because allergic reactions are possible, although they are rare. No topical analgesics should come into contact with the eyes, nose or mouth, so it is important for patients to wash their hands after applying the products.
Creams, gels and rubs that contain aspirin or other forms of salicylates should not be used by patients who take blood thinners. Salicylate products should not be used on children. Symptoms of salicylate toxicity include trouble breathing, blurry vision and tinnitus, or ringing in the ears. Patients who experience these symptoms when using a topical analgesic that contains aspirin should stop using the product and see their doctors as soon as possible.
Most topical pain relievers should not be used more than three or four times a day, particularly if the patient experiences skin irritation as a side effect. Patients might experience irritation, itching and redness when first using a topical analgesic, but these symptoms usually dissipate within a week. People who experience severe or persistent skin-related symptoms should discontinue use of the product.
Prescription topical analgesics include gels that contain non-steroidal anti-inflammatory drugs (NSAIDs). These are particularly suitable for patients who have arthritis or other inflammatory conditions and for patients who cannot use creams that contain salicylates. Pain-relieving patches that contain lidocaine help numb the area and are often helpful for patients who have shingles or joint pain.