Benzocain Sprays, Gels and Liquids Linked to Methemoglobinemia Risk: FDA

Federal health regulators are warning about continuing reports that the use a benzocain products, including sprays, gels and liquids, led to the development of methemoglobinemia, a rare and potentially life-threatening condition in which the amount of oxygen carried through the blood stream is greatly reduced.

In a safety alert issued on Friday, the FDA notified healthcare providers and consumers about the potential risk of methemoglobinemia from benzocain products, warning that they should not be used by children less than two, except under the advice and supervision of a doctor.

Benzocain products may be used as a spray during medical procedures to numb the mucous membranes of the mouth and throat, or as a gel or liquid sold over-the-counter to reduce pain associated with conditions like teething, canker soures or irritation of the mouth and gums.

Methemoglobinemia from benzocain have been mainly reported among children two years or younger who were being treated with benzocain gel for teething, but it has been linked to all strengths of the gel and liquids and it has been reported following the administration of only a single dose of benzocain spray.

Symptoms of methemoglobinemia can include:

• pale, gray or blue colored skin, lops and nail beds;
• headache
• lightheadedness
• shortness of breath
• fatigue
• rapid heart rate

In most severe cases of methemoglobinemia, the rare blood condition resulted in death.

The FDA indicates that it is continuing to review the safety of benzocain products, but warns consumers not to use the spray, gel or liquid benzocain on children under two years old, unless it is under the advice and supervision of a healthcare professional. In addition, consumers have been urged to store products out of the reach of children.

The agency has indicated that it will update the public when additional information is available, and will take appropriate regulatory action as warranted. Cases of methemoglobinemia or other problems from benzocain products should be reported to through the FDA MedWatch Safety Information and Adverse Event Reporting Program.