Powerful Non Drowsy Cough Medicine for Adults Robitussin Cough and Congestion Medicine DM is a cough suppressant and expectorant that provides fast effective relief from your worst cold symptoms. This non drowsy cough medicine for adults comes in a raspberry flavored liquid that is easy to measure and administer. For adults and children 12 years and older simply take 20 mL of this Robitussin expectorant and cough suppressant liquid every four hours as needed for symptoms. Robitussin Cough and Chest Congestion DM controls coughs with dextromethorphan a powerful cough suppressant and delivers chest congestion relief with the mucus relief expectorant guaifenesin. Formulated to control symptoms while letting you get on with your day this liquid expectorant and daytime chest congestion relief medicine is non drowsy. Delivering cough relief for more than 70 years Robitussin has the product you need to treat your specific cough cold sore throat or flu symptoms for day and night relief. Robitussin shuts cou