Experiences with
Cetirizine

About cetirizine

Cetirizine is an antihistamine medicine that helps the symptoms of allergies.

It's used to treat:

hay fever
conjunctivitis (red, itchy eye)
eczema
hives (urticaria)
reactions to insect bites and stings
some food allergies

Cetirizine is known as a non-drowsy antihistamine. It's much less likely to make you feel sleepy than some other antihistamines.

Cetirizine is available on prescription, but you can also buy it from pharmacies and supermarkets.

It comes as tablets, capsules and as a liquid that you swallow.

Who can and cannot take cetirizine

Most adults can take cetirizine.

Children

Children aged 1 and over can take cetirizine liquid if prescribed by their doctor.
Children aged 2 and over can take cetirizine liquid bought from pharmacies or prescribed by their doctor.
Children aged 6 and over can take cetirizine tablets and liquid that you buy from pharmacies and supermarkets.
Children aged 12 and over can take cetirizine capsules, tablets and liquid that you buy from pharmacies and supermarkets.

Who may not be able to take cetirizine

Cetirizine is not suitable for some people. To make sure it's safe for you, tell your doctor or pharmacist if you:

have ever had an allergic reaction to cetirizine or any other medicine
have an allergy to food additives
have an allergy to peanuts or soya – some brands of cetirizine capsules (but not tablets) contain soya
have kidney failure
have epilepsy or another health problem that puts you at risk of having seizures or fits
have a condition that means you have difficulty peeing
are due to have an allergy test – taking cetirizine may affect the results, so you might need to stop taking it a few days before the test

How and when to take cetirizine

If you or your child have been prescribed cetirizine, follow your doctor's instructions about how and when to take it. If it is from a pharmacy or shop, follow the instructions that come with the packet.

Dosage and strength

Cetirizine comes as tablets and capsules (10mg) and as a liquid medicine (labelled either 5mg/5ml or 1mg/1ml).

The usual dose for adults is 10mg once a day.

Doses are usually lower for people with kidney problems.

Children

For children between 6 to 11 years of age, the usual dose is 5mg, twice a day. Try to leave 10 to 12 hours between doses. So, one first thing in the morning, and one before bedtime.
For children between 2 to 5 years of age, the dose is 2.5mg, twice a day.
For children between 1 to 2 years of age, your doctor will use their weight or age to work out the right dose.

How to take it

You can take cetirizine with or without food, but always take the tablets or capsules with a drink of water, milk or squash. Swallow them whole. Do not chew them.

Cetirizine liquid may be easier for children to take than tablets. The liquid medicine will come with a plastic syringe or spoon to give the right dose. If you do not have a syringe or spoon, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure out the right amount.

When to take it

You may only need to take cetirizine on a day you have symptoms – for example, if you have been in contact with something that has triggered your allergy, like animal hair.

Or you may need to take it regularly to prevent symptoms – for example, to stop hay fever during spring and summer.

What if I forget to take it?

Take your forgotten dose as soon as you remember, unless it's nearly time for your next dose. In this case, skip the missed dose and take your next dose at the usual time.

Do not take 2 doses to make up for a forgotten dose.

If you forget to give a dose to a child who is taking cetirizine twice a day, you can give the missed dose if it's within 4 hours of when they should have had it.

If you remember more than 4 hours after, do not give the missed dose. Instead, wait until the next dose and carry on as normal.

If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

What if I take too much?

Cetirizine is generally very safe. Taking more than the usual dose is unlikely to harm you or your child.

If you take an extra dose, you might get some of the common side effects. If this happens or you're concerned, contact your doctor.

Side effects

Like all medicines, cetirizine can cause side effects, although not everyone gets them.

Common side effects

The most common side effect of cetirizine is feeling sleepy and tired. This happens in more than 1 in 10 people. Talk to your doctor or pharmacist if this side effect bothers you or does not go away.

Other common side effects of cetirizine happen in more than 1 in 100 people.

Talk to your doctor or pharmacist if these side effects bother you or do not go away:

headaches
dry mouth
feeling sick (nausea)
feeling dizzy
diarrhoea
sore throat
sneezing or blocked and runny nose

Children are more likely to get diarrhoea, sneezing or a blocked and runny nose than adults.

Serious side effects

It's rare to have a serious side effect with cetirizine.

Call your doctor straight away if you have bruising or bleeding that's more than normal.

Serious allergic reaction

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to cetirizine.

OLD Meds - Serious allergic reaction immediate care card (standard)

These are not all the side effects of cetirizine. For a full list, see the leaflet inside your medicines packet.

How to cope with side effects of cetirizine

What to do about:

feeling sleepy and tired – try a different non-drowsy antihistamine. If this does not help, talk to your doctor.
headaches – make sure you rest and drink plenty of fluids. It's best not to drink too much alcohol. Ask your pharmacist to recommend a painkiller for your headaches, but they usually go away after the first week of taking cetirizine. Talk to your doctor if your headaches last longer than a week or are severe.
dry mouth – chew sugar-free gum or suck sugar-free sweets.
feeling sick (nausea) – try taking your tablets with food. It may also help if you stick to simple meals and avoid rich or spicy food.
feeling dizzy – if cetirizine makes you feel dizzy when you stand up, try getting up very slowly or stay sitting down until you feel better. If you begin to feel dizzy, lie down so that you do not faint, then sit until you feel better. Do not drive, cycle or use tools or machines if you feel dizzy or a bit shaky.
diarrhoea – drink plenty of water or other fluids if you have diarrhoea. Speak to a pharmacist if you have signs of dehydration, such as peeing less than usual or having dark, strong-smelling pee. Do not take any other medicines to treat diarrhoea without speaking to a pharmacist or doctor.
sore throat – if you're 16 and over, you can try gargling with an aspirin solution (1 soluble aspirin tablet dissolved in half a glass of water) or use a pain-relieving mouthwash such as Oraldene. If your symptoms last longer than a week, ask your pharmacist or doctor for advice. Children under 16 must not be given aspirin.
sneezing or blocked and runny nose – try a different non-drowsy antihistamine. If this does not help, talk to your doctor.

Pregnancy and breastfeeding

Cetirizine can be used in pregnancy. There is no good evidence that it causes harm to the baby. However, other antihistamines such as loratadine may be recommended as there is more information about its use in pregnancy.

Cetirizine and breastfeeding

If your doctor or health visitor says your baby is healthy, you can take cetirizine while breastfeeding.

There is some information available which shows that only very small amounts get into breast milk. Cetirizine has been used for many years while breastfeeding without side effects in babies.

If your baby is not feeding as well as usual, seems unusually sleepy, or if you have any other concerns about your baby, talk to your doctor, pharmacist, health visitor or midwife.

OLD Meds - Pregnancy non-urgent care card

Cautions with other medicines

Some medicines can increase the chances of you having side effects with cetirizine.

Check with your pharmacist or doctor if you're taking any medicine that makes you drowsy, gives you a dry mouth, or makes it difficult for you to pee. Taking cetirizine might make these side effects worse.

Mixing cetirizine with herbal remedies and supplements

There might be a problem taking some herbal remedies and supplements alongside cetirizine, especially ones that cause sleepiness, a dry mouth, or make it difficult to pee.

OLD Meds - Cautions with other medicines alert