Ambroxol is a mucolytic which thins and loosens mucus (phlegm), making it easier to cough out. Dextromethorphan Hydrobromide is a cough suppressant that relieves cough by reducing the activity of cough center in the brain. Phenylephrine is a decongestant which narrows the small blood vessels providing relief from congestion or stuffiness in the nose. Chlorpheniramine Maleate is an antiallergic which relieves symptoms like runny nose, watery eyes and sneezing. Menthol produces a sensation of coolness and relieves minor throat irritation.