The fluoride varnish applied today covers moist teeth with a coating of protective film for several hours. Longer contact time provides greater protection.
Avoid brushing the treated teeth for four to six hours after application.
Mouthwashes or rinses containing alcohol can accelerate the dissolution of the fluoride varnish, and should be avoided for at least four hours after application.
Other fluoride preparations such as fluoride gels should not be administered during the same day. The routine use of fluoride tablets should be interrupted for 2-3 days after treatment.
Swelling has been reported only in rare instances in some fluoride varnish products. Nausea has also been reported. If required, varnish can be removed with a thorough brushing.