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Frequently Asked Questions


When you’re muddling through your allergies, all you want is an answer. Or maybe more than one. Here’s a quick list of responses to all your important questions about our products and what might be causing your allergies.

Questions about:

Questions about ZYRTEC®

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What is ZYRTEC®?

ZYRTEC® is an over-the-counter medicine that provides effective, 24-hour relief of indoor and outdoor allergy symptoms.

What allergy symptoms does ZYRTEC® relieve?

ZYRTEC® relieves your worst allergy symptoms of sneezing, runny nose, itchy, watery eyes, and itchy nose or throat.

Is ZYRTEC® an antihistamine?

Yes. ZYRTEC® contains cetirizine HCl, which is an antihistamine.

What is an antihistamine?

An antihistamine is a drug that blocks the action of histamine—an allergy-causing chemical that’s released by certain cells in the body. Antihistamines are used to treat runny nose, sneezing and other allergy symptoms.

Should I take ZYRTEC® with food?

Your choice. ZYRTEC® can be taken either with or without food.

How fast does ZYRTEC® start working?

ZYRTEC® begins to work at hour 1 on the first day you take it.

How long does ZYRTEC® last?

ZYRTEC® provides 24-hour relief, all day and all night.

Is it okay to take ZYRTEC® over a long period of time?

The ZYRTEC® package label doesn’t state a limit on how long you can take ZYRTEC®. Talk to your doctor if you have any questions, especially if you’re taking other medicines or being treated for any other conditions.

What’s the best time of day to take ZYRTEC®?

Any time of day works. And ZYRTEC® will continue to work for 24 hours.

Do I need a prescription to take ZYRTEC®?

No. Since 2008, ZYRTEC® has been available over the counter, without a prescription.

Is the over-the-counter version of ZYRTEC® the same as the prescription strength?

Yes. Today’s ZYRTEC® has the same exact strength as the version that required a prescription previously.

Can ZYRTEC® make me drowsy?

For information on side effects, please read the ZYRTEC® product label or review the product details on this site.

Can I use ZYRTEC® if it is expired?

No. If your ZYRTEC® has expired, please discard it properly and get a new package. (See next question.)

What is the proper way to dispose of unused or expired ZYRTEC® products?

Do NOT dispose of any ZYRTEC® product by emptying it into your sink, toilet or storm drain. Check to see if your pharmacy or community has a take-back program in which you can drop off your expired or unused medicine for them to dispose for you. Otherwise, place your medicine in an unmarked, sealed container and dispose of the container in your household trash. Visit the FDA website for more information.

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Questions about ZYRTEC® Dissolve Tabs

Do dissolve tabs work faster than tablets or liquid gels?

ZYRTEC® Dissolve Tabs provide the same fast relief as ZYRTEC® Tablets and ZYRTEC® Liquid Gels. All ZYRTEC® medicines start working at hour 1 on the first day you take it.

Can I chew or swallow the dissolve tabs? Or do they need to dissolve on my tongue first?

ZYRTEC® Dissolve Tabs are designed to dissolve in your mouth without chewing or drinking water, but it’s perfectly fine to chew or swallow them.

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Questions about ZYRTEC-D®

How is ZYRTEC-D® different from ZYRTEC®?

ZYRTEC-D® contains pseudoephedrine, which relieves nasal congestion. So it relieves all the same symptoms as ZYRTEC®, plus it also has a powerful decongestant. For more, see: “What symptoms does ZYRTEC® relieve?”

How does ZYRTEC-D® work on sinus pressure and congestion?

ZYRTEC-D® contains a nasal decongestant that narrows the blood vessels in the nose and sinus region, which shrinks the tissue in that area to allow air and mucus to flow normally.

Why is ZYRTEC-D® located behind the pharmacy counter?

Pseudoephedrine, an active ingredient in some cold, allergy, and sinus products, can be chemically processed into methamphetamine (commonly known as meth). The illegal use of meth had increased, prompting Congress to pass the Combat Methamphetamine Epidemic Act of 2006 (CEMA). The objective of the law is to eliminate the use of pseudoephedrine in the illegal production of meth. By law, products containing pseudoephedrine must now be sold behind the counter and through online retailers who must meet certain requirements.

Note that products containing pseudoephedrine remain available without a prescription in most states.

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Questions about Children’s ZYRTEC®

How can I be sure I’m giving my child the proper dose of Children’s ZYRTEC®?

Always follow the instructions that come with Children’s ZYRTEC®. When taking Children’s ZYRTEC® Allergy Syrup, be sure to use the dosing cup that comes in the package. Other items like kitchen teaspoons, droppers or measuring devices that come with other medicines may not be accurate. If you have any questions about treating your child’s allergies, please speak with your doctor.

Can Children’s ZYRTEC® make my child drowsy?

For information on side effects, please read the Children’s ZYRTEC® product label or review the product details on this site.

What’s the difference between Children’s ZYRTEC® Allergy Syrup and Children’s ZYRTEC® Dissolve Tabs?

Children’s ZYRTEC® Allergy Syrup can be taken by kids 2 years and older, whereas Children’s ZYRTEC® Dissolve Tabs is for ages 6 and up.

What’s the difference between ZYRTEC® Dissolve Tabs and Children’s ZYRTEC® Dissolve Tabs?

There is no difference. Both products contain 10mg of cetirizine in the same citrus flavor and can be taken by both adults and children 6 years and older.

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General Allergy Questions

How do I know if I have allergies?

If you find yourself sneezing a lot or have a consistently runny or stuffy nose, there’s a good chance you have upper respiratory allergies. Allergies affect more than 50 million people in the United States alone.

What are the common symptoms of upper respiratory allergies?

People with allergies can experience lots of symptoms, including sneezing, runny nose, stuffy nose (nasal congestion), or itchy, watery eyes.

What are outdoor allergies?

If you only develop upper respiratory symptoms at certain times of the year (often spring or fall), you probably have seasonal allergic rhinitis, or outdoor allergies. These allergies can be triggered by trees, grass and weed pollens, or outdoor mold. Learn more about outdoor allergies.

What are indoor allergies?

If you have symptoms all year round, it’s likely perennial allergic rhinitis, or indoor allergies. Common triggers include animal dander (tiny skin flakes or saliva from animals), indoor mold and dust mites. Learn more about indoor allergies.

What can I do to help relieve my outdoor allergies?

In addition to taking ZYRTEC®, you may want to:

  • Keep your windows closed and use air conditioning instead
  • Stay indoors during peak pollen hours (5 a.m. – 10 a.m.)
  • Change your clothes after you’ve been outside
  • Don’t hang your laundry outside to dry
  • Avoid mowing the lawn or raking leaves
  • Learn more outdoor allergy relief tips.

What can I do to help relieve my indoor allergies?

In addition to taking ZYRTEC®, you may want to:

  • Clean the filters in your air conditioner and heater regularly
  • Vacuum often, especially carpets and upholstered furniture
  • Keep your pets bathed and groomed
  • Run an air purifier
  • Crack open the bathroom window during showers
  • Learn more about indoor allergies.

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