Misc: Whiter teeth in 3 days. 2x whitening (vs. Optic White Sparkling Mint). Enamel safe. Gluten free. Some people may experience tooth sensitivity or gum discomfort when using whitening products. This discomfort is temporary and not harmful. If you experience more than mild tooth sensitivity, stop use and consult your dentist. Whiter teeth in three days (For best results, use as directed for 4 weeks). Professionally recommended whitening ingredient, hydrogen peroxide. Enamel safe for daily use. Save Water: www.colgate.com/savewater. Turning off your water while brushing your teeth can save up to 4 gallons of water each time you brush! www.colgateopticwhite.com. Made in Mexico.