Skip to main content

Cetirizine

Generic name: cetirizine [ se-TIR-a-zeen ]
Brand name: Zyrtec
Drug class: Antihistamines

Medically reviewed by Philip Thornton, DipPharm. Last updated on Sep 20, 2024.

What is cetirizine?

Cetirizine is a second generation antihistamine that reduces the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Cetirizine is used to treat cold or allergy symptoms such as sneezing, itching, watery eyes, or runny nose.

Cetirizine is also used to treat an allergic reaction, itching and swelling caused by chronic urticaria (hives) and minimizes or eliminates the symptoms of perennial allergic rhinitis, seasonal allergic rhinitis, chronic idiopathic urticaria, allergic asthma, physical urticaria, and atopic dermatitis.

Warnings

Cetirizine can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert. Avoid drinking alcohol. It can increase some of the side effects of cetirizine.

Tell your doctor if you regularly use other medicines that make you sleepy (such as other cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by cetirizine.

Call your doctor if your symptoms do not improve, if they get worse, or if you also have a fever.

Before taking this medicine

You should not use this medication if you are allergic to or had an adverse reaction to cetirizine.

Before taking cetirizine, tell your doctor about all of your medical conditions or if you have ever had kidney or liver disease.

Cetirizine is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Cetirizine can pass into breast milk and may harm a nursing baby. Do not use cetirizine without telling your doctor if you are breast-feeding a baby.

Cetirizine is indicated for chronic idiopathic urticaria in adults and children 6 months of age and older.

Older adults may need to take a lower than normal dose. Follow your doctor's instructions.

Cetirizine pregnancy and breastfeeding warnings (more detail)

How should I take cetirizine?

Take cetirizine exactly as directed on the label, or as prescribed by your doctor. Do not use it in larger amounts or for longer than recommended.

You may take cetirizine with or without food.

The chewable tablet must be chewed before you swallow it.

Oral doses: measure liquid medicine (oral solution) with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Call your doctor if your symptoms do not improve, if they get worse, or if you also have a fever. Store cetirizine at room temperature away from moisture and heat.

Detailed Cetirizine dosage information

prednisone, hydroxyzine, fluticasone nasal, cetirizine, loratadine, diphenhydramine, promethazine, Zyrtec, Xolair

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine or add extra doses to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include feeling restless or nervous, and then feeling drowsy.

What should I avoid?

Tell your doctor if you regularly use other medicines that make you sleepy (such as other cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by cetirizine.

Cetirizine can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Avoid drinking alcohol. It can increase some of the side effects of cetirizine.

Cetirizine acute and common side effects

Get emergency medical help if you have any serious adverse effects or any of these signs of an allergic reaction: chronic idiopathic urticaria (hives); difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using cetirizine and call your doctor at once if you have any of these serious side effects:

Less serious cetirizine side effects may include:

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.

Cetirizine side effects (more detail)

What other drugs will affect cetirizine?

There may be other drugs that can interact with cetirizine. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.

Cetirizine drug interactions (more detail)

Does cetirizine interact with my other drugs?

Enter medications to view a detailed interaction report using our Drug Interaction Checker.

Copyright 1996-2024 Cerner Multum, Inc. Version: 6.01.

Popular FAQ

How long does it take for cetirizine to work?

Cetirizine will start to work within one hour after you take it. It provides allergy relief for 24-hours. It relieves symptoms like sneezing, runny nose, itchy and watery eyes, and itchy nose or throat. If it makes you drowsy, you can take it at bedtime, or as directed by your doctor.

Can you take Benadryl and cetirizine together?

Benadryl should not be taken at the same time as cetirizine because it can increase side effects such as dizziness, drowsiness, and difficulty concentrating. Some people, especially the elderly or children, may also find their thinking, judgement, and coordination impaired. You should also not drink alcohol while taking either of these medications because it can make these side effects worse.

How long after taking cetirizine can I drink alcohol?

It is best to wait until cetirizine completely leaves your body before you drink alcohol, which may take up to 40 hours (almost 2 days). This is because alcohol can increase the nervous system side effects of cetirizine such as dizziness, drowsiness, and difficulty concentrating. Some people may also find it difficult to think or make good judgements. This calculation is based on the half-life of cetirizine, which is 8.3 hours, and experts say it takes 4 to 5 half-lives for a drug to fully leave your body which works out to 33 to 40 hours.

Does cetirizine make you drowsy?

Cetirizine is classed as a non-drowsy (non-sedating) antihistamine, but it does make some people drowsy. In clinical trials, this side effect appeared to be related to the dose of cetirizine, with higher dosages increasing the risk of feeling drowsy. 1.9% of children aged 6 to 11 years experienced drowsiness with 5mg of cetirizine and 4.2% of children experienced drowsiness with 10mg of cetirizine. Up to 14.3% of adults may be affected by drowsiness with cetirizine.

Can cetirizine raise blood pressure?

Cetirizine does not increase blood pressure and blood pressure is not listed as a side effect in the product information. But cetirizine can be found in combination with other medications, such as pseudoephedrine in products such as Zyrtec-D, and pseudoephedrine does increase blood pressure.

More FAQ

View more FAQ

Further information

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

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer