Benylin Chesty Coughs Non-Drowsy - 150 ml.Power Through Your Cold This Winter.Benylin Chesty Coughs Non-Drowsy works deep down to loosen phlegm, clear bronchial congestion, and make your cough more productive. It contains Guaifenesin (an expectorant) that helps loosen mucus (phlegm) from the lungs and make it easier to cough up. Also, Levomenthol helps you breathe more easily by easing congestion. A cough is a reflex action to clear your airways of phlegm and irritants such as dust. A chesty cough is a productive cough which means phlegm is produced to help clear your airways. Benylin Chesty Coughs Non-Drowsy 150 ml is for when you're suffering from a deep, chesty cough, but still want to get on with your normal daily routine.