FDA Warns of Methemoglobinemia with Benzocaine Topical Products

The FDA notified healthcare professionals and patients that it has continued to receive reports of methemoglobinemia associated with benzocaine products. In 2006, FDA issued a Public Health Advisory warning about methemoglobinemia with the use of benzocaine sprays during medical procedures. Since then, the FDA has received 72 new cases of methemoglobinemia, including three resulting in death, associated with the use of benzocaine sprays, bringing the total to 319 cases. A review of the cases indicates that the development of methemoglobinemia after treatment with benzocaine sprays may not be related to the amount applied. Symptoms of methemoglobinemia may appear within minutes to one or two hours after using benzocaine.

Healthcare professionals should advise patients and caregivers to use the smallest amount possible to relieve pain. Infants <4 months of age, elderly patients, and patients with certain inborn defects such as glucose-6-phosphodiesterase deficiency, hemoglobin-M disease, NADH-methemoglobin reductase (diaphorase 1) deficiency, and pyruvate-kinase deficiency may also be at greater risk of developing methemoglobinemia.. Benzocaine products should not be used on children <2 years of age, except under the advice and supervision of a healthcare professional. Healthcare professionals are advised to consider the American Academy of Pediatrics' recommendations for treating teething pain instead of using the benzocaine teething products.

Benzocaine is available as a spray, used during medical procedures to numb the mucous membranes of the mouth and throat, and in gel and liquid formulations sold over-the-counter (OTC) for the relief of teething, canker sores, and irritation of the mouth and gums. Benzocaine sprays are marketed under different brand names such as Hurricaine, Cetacaine, Exactacain, and Topex. Benzocaine gels and liquids are sold OTC under different brand names such as Anbesol (Wyeth), Hurricaine, Orajel (Del), Baby Orajel (Del), Orabase, and store brands.

For more information visit www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm250264.htm.