Piriteze Allergy Syrup Piriteze Allergy Syrup contains the antihistamine cetirizine hydrochloride to treat the allergic symptoms (itchy or watery eyes, sneezing & a stuffy nose) of hayfever & other allergies, e.g. pet, house dust mite & mould spore allergies. It can also be taken to relieve the rashes & itching of chronic urticaria (hives). Piriteze Allergy Syrup is a delicious banana flavour liquid that is ideal for children over the age of 6 years & adults who don't like, or have difficulty, taking tablets.