Zyrtec: 7 things you should know - Drugs.com- Zytec Händedesinfektionsspray Bezugsquellen ,Apr 08, 2020·1. How it works. Zyrtec is a brand (trade) name for cetirizine. Cetirizine is an antihistamine that works selectively on peripheral histamine-1 (H-1) receptors (these are histamine receptors that are located outside of the brain and spinal cord).: Zyrtec 24 Hour Allergy Relief Tablets, 10 mg ...Product Description. Zyrtec Allergy Tablets relieves your worst allergy symptoms, indoor and out. With 10 milligrams of cetirizine hydrochloride per tablet, this prescription-strength allergy relief medicine provides 24 hours of relief from common symptoms of hay fever and other upper respiratory allergies, including runny nose, sneezing, itchy, watery eyes, and itching of the nose or throat.