NOW Foods Xyliwhite Mouthwash Refreshmint Flavor - 16 oz. NOW Foods XyliWhite Mouthwash prevents the mouth's pH levels from falling below their normal range. NOW Foods XyliWhite Mouthwash protects the enamel surface of teeth. NOW Foods XyliWhite Mouthwash is a safe and effective fluoride-free oral rinse that works in unique ways to help you achieve a smile that's healthier and brighter than ever b