Levocetirizine may be found in some form under the following brand name: Xyzal. Levocetirizine is a medication used for the treatment of seasonal and indoor (perennial) allergies and hives. This medication belongs to a group of drugs called antihistamines. These work by blocking the action of histamine, a substance in the body that causes allergic symptoms such as sneezing, itching, runny nose, and watery eyes.