Get relief from chest congestion and a persistent cough with Mucinex® DM. Each 600 mg tablet features a unique bi-layer design: one side provides immediate release to start working right away, while the other side offers extended release for continuous relief that lasts for up to 12 hours. This formula combines Guaifenesin (600 mg), an expectorant that thins and loosens mucus to make coughs more productive, and Dextromethorphan HBr (30 mg), a cough suppressant that helps control the impulse to cough. Perfect for day or night, it allows you to break through congestion and go about your day without having to redose every few hours.