Officials at the U.S. Food and Drug Administration -- which regulates wart removers as medical devices -- said since 2009, the agency received 14 reports about over-the-counter wart remover products, which are a mixture of liquid dimethyl ether and propane.
Karen Nast, a nurse consultant at the FDA, said 10 patients have described singed hair, blisters, burns or skin redness. Nearby items have also caught fire, she said.
"The labeling for these products clearly states that they are flammable and should be kept away from fire, flame, heat sources, and cigarettes," Nast said in a statement. "In three of the reports, there was a candle nearby, but in the other 11 reports no ignition source was identified. This is extremely concerning, especially because people may not be aware that everyday household items like curling irons and straight irons can be hot enough to be an ignition source for these products."
Warts are growths caused by human papillomavirus infection. Most treatments using a mixture of liquid dimethyl ether and propane instruct users to follow certain steps.
Dr. Markham Luke, a dermatologist at the FDA, said warts can often disappear on their own without treatment in most people.
However, if you are not sure if your warts are cause for concern or if you have questions about using cryogenic products at home, it's best to be on the safe side and talk with your health care professional before taking action, Luke said.
A healthcare professional may prefer to remove the warts in the medical office, using treatments such as surgical paring, laser, or liquid nitrogen cryosurgical treatments.
"The advantage is that the healthcare professional has been trained in providing the treatment safely and under controlled conditions," Luke noted.