People who slather their skin with painkilling lidocaine gel might end up accidentally killing themselves, U.S. regulators said.
The gel and other topical anesthetics, used to relieve pain from medical procedures and tests, may cause life-threatening side effects when applied to a large area of the skin, the Food and Drug Administration said today on its Web site. Doctors should prescribe the lowest dose and patients should speak with health care providers before using the products for a mammogram, the FDA said.
Improper use of the anesthetics, available by prescription and on store shelves, may cause too much of the drug lidocaine to be absorbed into the bloodstream, leading to irregular heartbeats, seizures, breathing difficulties, coma or death, according to the FDA.
"FDA remains concerned about the potential for topical anesthetics to cause serious and life-threatening adverse effects when applied to a large area of skin or when the area of application is covered," according to the agency.
The FDA reported in 2007 that two women died after using topical anesthetics before laser hair removal.
More of the product's drug will pass into the bloodstream if applied over a large area, or if applied to broken skin, according to the agency.