Reactions 1704, p3 - 2 Jun 2018
Risk of methaemoglobinaemia with
OTC oral benzocaine
The US FDA has published a Drug Safety
Communication warning that the use of over-the-
counter (OTC) oral medications containing benzocaine
may be associated with methaemoglobinaemia.
Benzocaine is a local anaesthetic which may be used
for the temporary relief of pain, such as that associated
with soreness, injury or minor irritation of the mouth
and throat. Formulations include gels, lozenges,
ointments, solutions and sprays.
The FDA warns than benzocaine products should not
be used in patients <2 years of age. Manufacturers are
urged to stop marketing the products for the treatment
of teething in young children; lack of compliance may
result in removal of the products from the market.
Labelling changes for use in older patients include
adding a warning about methaemoglobinaemia, and
adding contraindications and revising the directions for
use in teething and in patients <2 years of age. A
standardised methaemoglobinaemia warning will be
included in the prescribing information for all
prescription local anaesthetics.
Consumers using benzocaine products are advised to
seek medical attention if signs of symptoms occur.
These include the following: shortness of breath;
headache; fatigue; confusion; or pale, grey or blue-
coloured skin, lips and nail beds. Symptoms may appear
within minutes of use, or within 1
2 hours. Healthcare
professionals should warn patients about the potential
risk, particularly in those with breathing problems or
heart disease, or the elderly.
Investigation of safety issues will continue, and the
public will be updated if additional information becomes
available. Patients and healthcare professionals are
urged to report any further adverse events involving
benzocaine to the FDA MedWatch program.
* Brand names include Anbesol, Hurricaine, Orabase, Oragel and Baby
Oragel, and Topex.
US Food & Drug Administration. Oral Over-the-Counter Benzocaine Products:
Drug Safety Communication - Risk of Serious and Potentially Fatal Blood
Disorder Internet Document : 23 May 2018. Available from: URL: https://
Reactions 2 Jun 2018 No. 17040114-9954/18/1704-0001/$14.95 Adis © 2018 Springer International Publishing AG. All rights reserved