Some rare childhood cancers on the decline

The US Food and Drug Administration (FDA) recommends that parents and caregivers not administer over-the-counter benzocaine-containing products to children younger than 2 years to relieve pain from teething, except under supervision of a health care professional.

Using the local anesthetic can lead to a rare but sometimes fatal condition known as methemoglobinemia in which an excess amount of methemoglobulin in the bloodstream inhibits oxygen delivery to tissues.

FDA first warned about the condition in connection with benzocaine in 2006. Since then, the agency has received 29 reports of benzocaine-related methemoglobinemia-19 of those occurred in children, 15 of which occurred in children younger than 2 years. FDA issued another warning in 2011.

The danger isn’t limited to children. Health care providers frequently use benzocaine-containing products to numb the mouth or throat during procedures such as transesophageal echocardiograms, endoscopy, intubation, and feeding tube replacement. Children are most at risk, but adults with heart disease, those who smoke, and those who have breathing conditions such as asthma, bronchitis, and emphysema are also at higher risk. Adults who use these products should keep them out of children’s reach.

Symptoms of methemoglobinemia include pale, gray, or blue-colored skin, lips, and nail beds; shortness of breath; fatigue; confusion; headache; light-headedness; and rapid heart rate. Symptoms may occur within minutes or hours after benzocaine use and may occur after first use or after many uses. FDA says that if any of these symptoms occur after using a benzocaine-containing product to stop use and call 911 immediately.

As alternatives to benzocaine-containing products, the American Academy of Pediatrics recommends using chilled, but not frozen, teething rings or gentle massage of the gums with a finger to help assuage teething children.

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