Thanks so much for using the Crest Pro-Health Advantage Multi-Protection Mouthwash! We appreciate your feedback and would like to learn more about your experience to pass along to our teams. Please know that our products undergo extensive testing and monitoring to ensure safety and effectiveness, and while it's great to know you're pleased with this rinse, there shouldn't be any aftertaste. We recommend you discontinue using the product and hold on to it in case we need to retrieve it. Also, when you have time, give us a call for further assistance at 1-800-492-7378, M - F, 9 a.m. to 6 p.m. EST.