But if, instead, you experience burning pain or blistering, you must seek medical attention immediately.
The Food and Drug Administration (FDA) is warning that some consumers have reported receiving serious skin injuries while using certain over-the-counter (OTC) pain relievers applied to the skin to relieve mild muscle and joint pain.
The injuries, while rare, have ranged from mild to severe chemical burns with use of such brand-name topical muscle and joint pain relievers as Icy Hot, Bengay, Capzasin, Flexall, and Mentholatum.
OTC topical pain relievers for muscles and joints include creams, lotions, ointments and patches. In many cases, burns where the product was applied occurred after just one application, with severe burning or blistering occurring within 24 hours. Some had complications serious enough to require hospitalization.
"There's no way to predict who will have this kind of reaction to a topical pain reliever for muscles and joints," says Jane Filie, M.D., a medical officer in FDA's Division of Nonprescription Regulation Development (DNRD).
According to FDA chemist Reynold Tan, Ph.D., there have been 43 reported cases of burns associated with the use of OTC topical muscle and joint pain relievers containing the active ingredients menthol, methyl salicylate and capsaicin. These cases were uncovered by FDA scientists during safety surveillance of FDA's adverse event reporting database and the medical literature.
This is a very small number of cases when compared to the number of people who purchase these products, Tan notes.
Menthol, methyl salicylate and capsaicin create sensations of local warmth or coolness, but should not burn.
According to the available data, a majority of the more severe burns occurred with the use of a menthol or menthol/methyl salicylate combination product. Most of these cases involved products that contain higher concentrations of menthol and methyl salicylate (greater than 3% menthol or 10% methyl salicylate). Few of the cases involved capsaicin.
FDA has the following advice for consumers using OTC topical muscle and joint pain relievers:
- Don't apply these products onto damaged or irritated skin.
- Don't apply bandages to the area where you've applied a topical muscle and joint pain reliever.
- Don't apply heat to the area in the form of heating pads, hot water bottles or lamps. Doing so increases the risk of serious burns.
- Don't allow these products to come in contact with eyes and mucous membranes (such as the skin inside your nose, mouth or genitals).
- It's normal for these products to produce a warming or cooling sensation where you've applied them. But if you feel actual pain after applying them, look for signs of blistering or burning. If you see any of these signs, stop using the product and seek medical attention.
- If you have any concerns about using one of these products, talk to a medical professional first.
- Report unexpected side effects from the use of OTC topical pain reliever to the FDA MedWatch program
This article appears on FDA's Consumer Updates page, which features the latest on all FDA-regulated products.