DEXTROMETHORPHAN HYDROBROMIDE contains an anti-tussive (relieve cough) medication primarily used to treat dry cough. A cough is a reflex action that helps to clear any foreign irritant or mucus in the throat. Mostly cough lasts for a short time (two to three weeks), so it is acute. But sometimes, if it is persistent for more than eight weeks it can lead to chronic cough. A dry cough is tickly and doesn't produce any vicious or thick mucus.