Cetirizine
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![A package of 10 mg cetirizine tablets](/Images/godic/202502/19/Cetirizine103011.JPG")
![Zyrtec-D, a combination of cetirizine and pseudoephedrine](/Images/godic/202502/19/Zyrtec-D_blister_pack3011.png")
Cetirizine /sɛˈtɪrᵻziːn/ (trade names Zirtec, Zyrtec, Reactine) is a second-generation antihistamine used in the treatment of hay fever, allergies, angioedema, and urticaria. It is a major metabolite of hydroxyzine, and a racemic selective H1 receptor antagonist.