For temporary cough relief and to help loosen phlegm from your bronchial passageways, turn to DayQuil Mucus Control DM.; Helps loosen phlegm (mucus) and thin bronchial secretions to rid the bronchial passageways of bothersome mucus; Temporarily relieves cough associated with the common cold; When using other DayQuil or NyQuil products, carefully read each label to insure correct dosing.