Is fluoride varnish safe?

Background Fluoride varnish is widely used in dentistry as a caries preventive measure with recommendations for its use even in infants. In addition, nondental providers are also applying varnish on children's teeth in various settings. However, there are questions from these nondental providers as to the safety of fluoride varnish. Methods To evaluate and describe the adverse events (AEs) related to fluoride varnish, the US Food and Drug Administration’s Manufacturer and User Facility Device Experience database was used. AEs reported for the dental product code for “varnish, cavity,” “varnish,” and “fluoride” were evaluated. The identified AEs were then reviewed and categorized using appropriate key words for the various signs and symptoms, outcomes, and treatment. Results Over the 10-year period, only 65 AEs were reported for fluoride varnish products. Swelling (33.8%); burning, itching, or soreness (23.1%); and rash (16.9%) were the most common signs and symptoms reported. The most common site reported was the lips (27.7%). The most common outcome was that the patient was taken to the hospital (18.5%) or emergency department (15.4%). No deaths were reported. The patients were treated primarily using diphenhydramine (Benadryl, Johnson & Johnson Consumer) (26.1%), followed by an epinephrine autoinjector (EpiPen, Mylan) and other forms of epinephrine (15.4%), and prednisolone (9.2%). In 16.9% of the cases with AEs there was a history of allergies. The rate of AEs is estimated to be between 0.099 and 0.105 per million for fluoride varnish. A concern is the likelihood of underreporting AEs in the Manufacturer and User Facility Device Experience database. Conclusions Given the widespread use of fluoride varnish in the United States, the number of AEs reported to the US Food and Drug Administration were few. Thus fluoride varnish can be considered a safe dental product. Practical Implications Provides data on the safety of fluoride varnish that can be used by the dental profession to allay concerns by nondental providers and patients on this important caries preventive measure.