BENYLIN^® Day & Night Tablets help reduce temperature, relieve aches and pains, help clear congestion and so make it easier to nod off at night. How it works? Diphenhydramine helps to relieve a runny nose, whilst pseudoephedrine causes the blood vessels in the nasal and sinus passages to contract and narrow, reducing congestion and the production of excess mucus. Paracetamol helps bring down a fever and provide relief from headaches or bodily aches and pains.