CariFree Boost Mouth Spray by Oral BioTech is a xylitol-containing mouth spray that can be used throughout the day or night as needed to relieve symptoms of dry mouth, or to help neutralize decay-causing acids after eating and drinking. CariFree Boost is an effective way to neutralize the effect of harmful decay-causing acid bacteria. For added protection, simply spray before bed. Individuals who have had chemo or radiations therapy can also benefit by using CariFree Boost. Convenient size, easy to carry in purse or pocket. Each box contains four 0.4 fl oz (12 mL) spray bottles with approximately 100 sprays per bottle.