Warn patients who use menthol(Drug information on menthol) rubs to ease muscle and joint pain that these topical ointments can sometimes cause serious burns, the FDA warned on September 13. Doctors are responsiblt for warning patients to use these rubs appropriately, the Agency added: Not to apply them to irritated skin or near eyes or mucous membranes, and not to use a heat lamp or heating pad at the same site or to put a bandage on top. The warning applied to products containing menthol, but not to those containing capsaicin.
Used safely, however, a topical menthol rubs can improve physical function for people with osteoarthritis of the knee, according to a placebo-controlled study that was published a day before the warning, by a team of physical therapists and nurses from Bellarmine University in Louisville and Marquette University in Milwaukee.The small study involving 20 patients tested on two occasions a week apart with a 3.5% menthol gel and a gel containing an inert substance, applied in random order.
There were no significant differences in baseline measures of pain. However, the menthol gel achieved significant improvements in pain and function during physical tasks such as a timed standing up from a chair exercise and going down stairs. The placebo gel had no effect.