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, as well as indoor allergens like dust, mold, and pet dander. This effective antihistamine features the active ingredient levocetirizine dihydrochloride, which starts working in just 45 minutes and provides 24-hour relief from allergy symptoms including sneezing; itchy, watery eyes; runny nose; and itchy nose or throat. Take Xyzal Original Prescription Strength at night for relief while you sleep and continued relief the next day, so you can wake up refreshed and ready for a more productive day. Be wise all, take Xyzal.