We always want our consumers to have a comfortable and enjoyable experience when using our products, and we are disappointed to hear that you have had some discomfort and excessive foaming while using our Crest Multi-Protection Mouthwash. While all of our products go through rigorous testing to ensure their safety, some consumers may be more prone to irritation from certain formulas than others. It is also normal to see a small amount of foaming with this mouth rinse as it contains CPC, but Since you have had some discomfort we would recommend discontinuing the use of the product and consulting with a dental professional to see if they can make a recommendation for your specific needs. We would love a chance to learn more about your experience so we are better able to assist you and get additional information to our Quality and Safety Teams. We encourage you to give us a call at (800) 285-9139.