Cetirizine Tablets/ Oral Solution

Cetirizine is a widely used antihistamine tablet that helps relieve the symptoms of allergies. It's commonly taken for hay fever, allergic rhinitis (a blocked or runny nose caused by an allergy), hives (itchy skin rashes), and other allergic reactions. It works by blocking histamine — the chemical your body releases when it reacts to something you're allergic to — helping to ease symptoms like sneezing, a runny or itchy nose, watery eyes, and itchy skin. Cetirizine starts to work within one hour of being taken and provides allergy relief for 24 hours.

For allergic rhinitis and urticaria, the usual adult dose of cetirizine is 5 to 10 mg taken orally once a day — the maximum recommended dose is 10 mg daily. You can take it with or without food, and it should be swallowed whole with a drink of water. Try to take it at the same time each day. If you're giving cetirizine to a child, the dose will be lower and depend on their age and weight — always check the packaging or ask your pharmacist for guidance.

Cetirizine is classed as a second-generation, low-drowsiness antihistamine, but it's worth knowing it can still cause sleepiness in some people — more so than some other modern antihistamines like fexofenadine or loratadine. The most common side effect is feeling sleepy and tired. Most people are absolutely fine, but it's sensible to see how cetirizine affects you personally before driving or operating machinery, especially when you first start taking it. Avoid alcohol while taking cetirizine as it can make any drowsiness worse.

Most people take cetirizine without any problems. Commonly reported side effects include headache, dry mouth, drowsiness, and fatigue. These tend to be mild and often settle down as your body gets used to the medication. In rare cases, a serious allergic reaction can occur — if you notice swelling of the face, lips, tongue or throat, or have difficulty breathing, stop taking cetirizine and call 999 or go to your nearest A&E immediately.

Yes, most people can take antihistamines every day if they have daily allergy symptoms. However, it's worth being aware that stopping cetirizine after prolonged use — typically beyond six months — may result in rare but severe generalised itching. This generally begins within a few days of stopping the medication. If you've been taking cetirizine for a long time and want to stop, it's a good idea to speak to your doctor first.

If you have kidney or liver problems, you should speak to your doctor before taking cetirizine. The kidney primarily excretes cetirizine, so the risk of side effects may be higher in people with impaired kidney function, who may need to take a lower dose. Your GP or one of our clinicians at Access Doctor can advise on the right dose for you.

If you're pregnant, ask your doctor or pharmacist for advice before taking cetirizine, as medicines can affect the unborn baby. If you're breastfeeding, you should not take cetirizine as it can be passed into breast milk. If you're suffering from allergy symptoms during pregnancy or while breastfeeding, speak to your GP who can recommend the safest treatment option for you.