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What Is Cetirizine?

Brand Name: Zyrtec, Aller-Tec, Alleroff
Generic Name: Cetirizine, Cetirizine Hydrochloride

Cetirizine is an antihistamine. It blocks the activity of histamines or inflammatory chemicals that cause inflammation reactions in the body due to exposure to allergens. The medication is sold on its own or in combination with pseudoephedrine to relieve sinus pain and pressure (MedlinePlus, 2010).

Read the FDA description of Cetirizine.

Are your allergy meds costing you too much? Find out how you can spend less at the pharmacy »

What Does Cetirizine Do?

When the body is exposed to an allergen such as pollen, mold, pet dander, or ragweed, the body releases histamines. These chemicals cause symptoms such as a runny nose, itchy eyes, and an itchy throat. Cetirizine works to block the effectiveness of histamines in the body, reducing allergic symptoms. However, cetirizine does not treat hives or allergic skin reactions.

This information is a summary. Before starting this medication, discuss questions with your healthcare provider and make sure you understand dosage instructions.

What Should I Tell My Doctor Before Starting Cetirizine?

Tell your doctor if you:

  • are breastfeeding
  • are pregnant or are planning on becoming pregnant
  • have kidney or liver disease
  • have a known hypersensitivity to cetirizine or hydroxyzine (Vistaril)

Patients with narrow-angle glaucoma or urinary retention or who take MAOI inhibitors should avoid taking cetirizine with pseudoephedrine

What Medications May Interact with Cetirizine?

Always tell your physician about any prescription medications or herbal remedies you are taking.

Medications that can adversely interact with cetirizine include:

  • theophylline (Theo-24, Theolair)

The FDA has not found any significant drug interactions with cetirizine. Always report any unexpected side effects to the FDA.

Cetrizine can cause drowsiness when mixed with alcoholic beverages.

Possible Side Effects of Cetirizine

The following are severe and emergent side effects of these medications. Contact your medical provider immediately if you experience the following:

  • symptoms associated with an allergic reaction, such as difficulty breathing or swallowing

The following side effects may occur, but do not usually represent an emergency. Discuss with your doctor or healthcare professional if they continue or are bothersome.

  • diarrhea
  • dizziness
  • drowsiness
  • dry mouth
  • excessive fatigue
  • stomach upset
  • vomiting

This list may not describe all possible side effects. Call your doctor or healthcare provider for advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Where Should I Keep Cetirizine?

Cetirizine should be stored at room temperature—somewhere around 68 degrees and 77 degrees Fahrenheit or 20 degrees and 25 degrees Celsius.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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