Fluoride is a drug used to prevent tooth decay. It is available on a nonprescription basis in many toothpastes. It is absorbed by teeth and helps strengthen teeth to resist acid and block the cavity-forming action of bacteria. As a varnish or a mouth rinse, fluoride helps reduce tooth sensitivity. Prescription-strength fluoride is available as a liquid, tablet, and chewable tablet to take by mouth. It usually is taken once daily. It is prescribed for children and adults whose homes have water that is not fluoridated (has not had fluoride added to water).
