Benylin Day and Night Tablets are used for the relief of cold and flu symptoms. The white day time tablets contain paracetamol, an analgesic and antipyretic which helps to relieve pain and fever and pseudoephedrine hydrochloride, a decongestant which unblocks stuffy noses. The blue night time tablets contain paracetamol and diphenhydramine hydrochloride, an antihistamine which helps clear catarrh and so aids sleep. This medicine is for use in adults and children aged 12 years and over.