MAX TUSSIN DM contains a combination of dextromethorphan and guaifenesin. Dextromethorphan is a cough suppressant and guaifenesin is an expectorant. MAX TUSSIN DM is used to treat cough and chest congestion caused by minor throat and bronchial irritations, the common cold, and allergies. MAX TUSSIN DM helps loosen phlegm (mucus) and thin bronchial secretions to help drain bronchial tubes.