What It Is
Cetirizine belongs to a class of medicines called antihistamines, specifically a newer generation often described as less sedating compared to older antihistamines.
What It's Used For
Cetirizine is generally used to relieve symptoms of allergies, such as sneezing, runny nose, itchy or watery eyes, and itching related to hives or other allergic skin reactions.
How It Works
Cetirizine works by blocking histamine receptors, specifically a type called H1 receptors. Histamine is a chemical the body releases during an allergic reaction, and it's responsible for triggering many of the familiar symptoms of allergies, including itching, swelling, and increased mucus production. By blocking histamine from binding to its receptors, cetirizine prevents these symptoms from being triggered, or reduces their severity.
History and Regulatory Status
Cetirizine was developed as part of a broader effort to create antihistamines that caused less drowsiness than older medicines in the same class, which often crossed more readily into the brain and caused significant sedation. It was introduced for clinical use in the late 1980s in Europe, with wider international availability following in subsequent years. It has since become available over the counter in many countries, reflecting a long track record of use, and remains one of the most commonly used antihistamines worldwide for managing seasonal and other allergy symptoms.