cetirizine

noun

ce·​tir·​i·​zine se-ˈtir-ə-ˌzēn 

variants or less commonly cetirizine hydrochloride

: a long-acting, nonsedating, antihistamine drug taken orally in the form of its hydrochloride C₂₁H₂₅ClN₂O₃·2HCl especially to treat allergic rhinitis and chronic hives

Note: Cetirizine is marketed under the trademark Zyrtec.

Examples of cetirizine in a Sentence

Recent Examples on the Web

Other common side effects of cetirizine and levocetirizine include fatigue, drowsiness, cough, dry mouth, fever, sore throat, nosebleed, diarrhea and vomiting, per the FDA. —Melissa Rudy, FOXNews.com, 23 May 2025

The affected medicines include cetirizine, which is popularly sold under the brand name Zyrtec, and levocetirizine, sold as Xyzal. —Melina Khan, USA Today, 22 May 2025

For example, a child taking an antihistamine like Zyrtec (cetirizine) may need to stop taking it for a few days before their test. —Ruth Jessen Hickman, Md, Health, 17 Apr. 2025

Common medications include Flonase (fluticasone propionate), Allegra (fexofenadine), Claritin (loratadine), Zyrtec (cetirizine), and Benadryl (diphenhydramine).9 Antidepressant and antipsychotic medications: These affect your central nervous system and the blinking function of your eyes. —Cristina Mutchler, Health, 1 Apr. 2025

Zyrtec contains cetirizine, whereas Xyzal contains levocetirizine, a more potent form of cetirizine.23 Xyzal will work as well as Zyrtec at lower doses and is sometimes better tolerated. —T'keyah Bazin, Pharmd, Verywell Health, 10 Mar. 2025

Second-generation antihistamines such as Zyrtec (cetirizine), Allegra (fexofenadine), and Claritin (loratadine) are less likely to cause drowsiness. —Alex Yampolsky, Verywell Health, 4 Mar. 2025

For long-term treatment of allergy symptoms, your healthcare provider may recommend a second- or third-generation antihistamine, such as Zyrtec (cetirizine) or Xyzal (levocetirizine), respectively. —Jessica Swirble, Verywell Health, 11 Feb. 2025

Oral antihistamines: Medications such as Claritin (loratadine), Zyrtec (cetirizine), or Allegra (fexofenadine) tend to cause less sleepiness and other side effects compared to older antihistamines like Benadryl (diphenhydramine). —Daniel More, Verywell Health, 15 Jan. 2025

Word History

First Known Use

1987, in the meaning defined above

Medical Definition

cetirizine

noun

ce·​tir·​i·​zine se-ˈtir-ə-ˌzēn 

: a long-acting, nonsedating, antihistamine drug that is taken orally in the form of its dihydrochloride C₂₁H₂₅ClN₂O₃·2HCl especially to treat allergic rhinitis and chronic hives

Note: Cetirizine is a derivative of piperazine and an H₁ antagonist that binds competitively with histamine to H₁ receptors on cell membranes. It is marketed under the trademark Zyrtec.