Experience a night and day difference in allergy relief with Xyzal 24 Hour Allergy Relief Medicine, Original Prescription Strength Antihistamine, Levocetirizine Dihydrochloride Tablets. Xyzal provides prescription strength relief from outdoor allergens such as pollen, ragweed, grass and trees and indoor allergens such as dust, mold and pet dander. Xyzal allergy tablets are an effective antihistamine with active ingredient levocetirizine dihydrochloride that starts working in 45 minutes and provides 24-hour relief of allergy symptoms including sneezing; itchy, watery eyes; runny nose; itchy nose or throat. Take Xyzal original prescription strength at night for allergy symptom relief while you sleep and all the next day so you wake feeling refreshed and ready for a more productive day. Be wise all, take Xyzal.