Health Canada Reminder on Risks of Some OTC Topical Pain Relievers (for teething, burns, bites, etc.)

I had no clue the side effects of a topical pain reliever - benzocaine - could be so serious, or that it was under review by Health Canada. Perhaps you didn't either.

Food for thought (from HSW) next time you reach for medication to treat the pain associated with sore throats, teething, toothache, burns, and insect bites.

Event Highlights

Health Canada is reminding Canadians, including parents and caregivers, about health risks associated with the use of topical benzocaine products, including a rare but potentially serious blood condition known as methemoglobinemia (MetHb). Health Canada continues to receive reports of benzocaine-related adverse reactions, including MetHb. Health Canada reports that it will continue to evaluate the safety of benzocaine products in light of these reports and will take appropriate regulatory actions as warranted.

Topical benzocaine products are available over-the-counter in various concentrations and formulations, including sprays, gels, liquids and creams, and are used to relieve pain from a variety of conditions such as sore throats, teething, toothache, canker sores, irritation of the mouth and gums, burns, insect bites, itching, and hemorrhoids. They are also used by healthcare practitioners during surgical, dental and other medical procedures to numb the mouth and throat.

Health Canada first communicated the risk of MetHb in a Public Advisory and Notice to Hospitals in November 2006. Since that time, Health Canada has received ▲seven reports of serious adverse reactions involving topical benzocaine, four of which were reports of benzocaine-induced MetHb in adults.

MetHb reduces the ability of red blood cells to deliver oxygen throughout the body. Signs and symptoms of MetHb include pale, grey or blue-coloured skin, lips, or nail beds; shortness of breath; fatigue; confusion; headache; lightheadedness; nausea; and change in heart rate. These symptoms can appear within minutes or one to two hours after benzocaine use, and can occur after the first or several uses. In rare severe cases, MetHb can progress to stupor, coma and possibly death.

Other reported side effects associated with topical benzocaine products include breathing or swallowing difficulties, a swollen tongue or mouth, irregular heartbeat, malaise, body twitching, hypersensitivity, burning, redness, itching, rash, and irritation at the site of administration. These effects can occur with any topical benzocaine product, regardless of product type or benzocaine concentration, in sensitive individuals.

Recommended Action:As with any health product, Canadians are reminded to carefully read and follow the instructions for product use. If you think you or your child may be experiencing a side effect, including signs or symptoms of methemoglobinemia, seek medical attention. If you have questions or concerns about a topical benzocaine product, speak to a healthcare practitioner.

For a list of Health Canada-licensed benzocaine products, including topical over-the-counter products, visit Health Canada's Licensed Natural Health Products Database (search by the ingredient name "benzocaine") and Drug Product Database (search by the active ingredient "benzocaine").

To report suspected adverse reaction to these or other health products, please contact Health Canada's Canada Vigilance Program toll-free at 1-866-234-2345, or complete a Canada Vigilance Reporting Form .