Effective and safe preventive fluoride programs require an awareness of the exact concentration of drinking water either public or bottled. When prescribing fluoride supplements, dentists should be aware of the fluoride content of bottled waters used by child patients, especially brands with a concentration higher than 0.3 ppm. In addition, the fluoride content of the bottled water may be highly variable among different brands, and that may cause dental fluorosis especially in infants and children when receiving greater concentration than the optimal levels recommended for their age group. Manufacturers are encouraged to the fluoride levels of the products may not be legally required in some countries and even when fluoride concentration appears on the bottle labels, they may not always be accurate.