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What is Cetirizine?

Going by the full name cetirizine hydrochloride, cetirizine is an antihistamine medicine1 used to relieve allergy symptoms caused by hay fever and hives2. It’s also a non-drowsy antihistamine for most people1.

While cetirizine can be prescribed by your doctor, it’s also readily available over the counter as capsules, tablets, and liquid that you swallow1.

Let’s look at how cetirizine hydrochloride works in the body, and its importance in managing allergic reactions.

In this guide:

What is cetirizine used for?

Cetirizine is used to relieve the symptoms of allergic reactions such as itchy eyes or nose, body itching, hives break out, runny nose, and watery eyes3.

How does cetirizine hydrochloride work?

Cetirizine relieves allergy symptoms by blocking histamine3, a natural substance in your body. Histamine is usually released by the body when it detects something harmful, such as an infection. It can cause your skin to swell as your blood vessels expand to protect the body2.

For people with allergies, though, the body mistakes something harmless like dust or pollen as harmful, releasing histamine. This causes an unpleasant allergic reaction with accompanying symptoms2.

While cetirizine is effective at treating some allergy symptoms, it cannot prevent or treat a more serious allergic reaction, such as anaphylaxis3.

How to take over the counter cetirizine

If you’re taking over the counter cetirizine such as BENADRYL® One a Day tablets to relieve your allergy symptoms, make sure you’re following the below advice:

  • Read all directions on the product package carefully before taking the medication.
  • If you have any questions about the product, consult your pharmacist3.

Potential cetirizine side effects

As is the case with all types of medicine, cetirizine can cause side effects in some people. Common side effects of taking cetirizine can include1:

  • Dry mouth
  • Headaches
  • Dizziness
  • A sore throat and sneezing
  • Feeling sick
  • Diarrhoea

Additionally, while cetirizine is classified as a non-drowsy antihistamine for most people1, others still find that it makes them feel sleepy and tired1.

If these side effects are causing you bother or don’t resolve themselves, consult your GP or a pharmacist1.

Loratadine vs cetirizine

Cetirizine and loratadine are both non-drowsy (in most people) antihistamines which are less likely to make you feel sleepy than first generation antihistamines2.

If you’re pregnant or planning to have a baby, ask your doctor or pharmacist for advice before taking either of the two2 Medicines can affect the unborn baby. Always talk to your doctor or pharmacist before taking any medicine in pregnancy. You also shouldn’t take cetirizine (including BENADRYL® One a Day ) when breastfeeding, as it can pass into breast milk.

Cetirizine FAQs

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