Cetirizine: Hay fever relief tablets

Cetirizine is suitable for both adults and children. Oral liquid tends to be the preferred option for children as they may find it difficult to swallow tablets. Age restrictions vary slightly depending on the product you are buying, but there are cetirizine products available over-the-counter for ages 2 and upwards.

Hay fever symptoms occur due to your body having an allergic reaction to pollen. During an allergic reaction, your immune system releases a chemical called histamine, which is responsible for the symptoms of an allergy. Antihistamines stop histamine binding to its target sites in your body, reducing the immune response that causes your allergic symptoms.

The chemical structure of non-drowsy antihistamines makes them less likely to enter the brain through what is known as the blood-brain barrier. This makes them less likely to cause drowsiness compared to other antihistamines.

As always, do not take any medication if you are allergic to any of the ingredients in it. Cetirizine should not be given to children under 2 years of age.

You should speak with your doctor or pharmacist before taking cetirizine if are pregnant or breastfeeding, if you have had an allergic reaction to another antihistamine in the past, or you are due to have an allergy skin test.

You should also speak with your doctor or pharmacist before taking cetirizine if you have liver or kidney problems, epilepsy, or difficulty passing urine, as it may not be suitable for you.

Many cetirizine tablets contain lactose, so people with lactose intolerance should avoid them. In this case, other formulations may be more appropriate. Cetirizine can interact with other medicines such as betahistine (used for Ménière's disease), certain antidepressants (called monoamine oxidase inhibitors), and dalteparin (an anticoagulant). If you take any prescription, over-the-counter, or herbal medicines, it is best to ask your doctor or pharmacist whether it is safe for you to take cetirizine.

Like all medications, cetirizine can cause side effects. Nausea, diarrhoea, headache, dizziness, and dry mouth are all common side effects you may experience from taking cetirizine. Also, despite being classed as a non-drowsy antihistamine, cetirizine can still cause drowsiness in some people. However, you are less likely to experience drowsiness from taking a non-drowsy antihistamine like cetirizine than you are from taking a drowsy one like chlorphenamine.