Cetirizine

Date: November 2018, Version 3

What is it?

Cetirizine (Benadryl one-a-day®, Zirtek®, Piriteze®, Pollenshield®) is a non-drowsy antihistamine used to treat allergies.

When deciding whether to use cetirizine during pregnancy it is important to weigh up the potential benefits to your health and wellbeing against any possible risks to you or your baby, some of which may depend on how many weeks pregnant you are. Your doctor or specialist will be able to help you make decisions about your treatment.

What if I have already taken cetirizine during pregnancy?

If you are taking any medicines while pregnant you can discuss this with your doctor. You can then decide together whether ongoing treatment is appropriate, and, if so, your doctor will ensure that you are taking the most effective dose.

Can taking cetirizine in pregnancy cause birth defects in the baby?

A baby’s body and most internal organs are formed during the first 12 weeks of pregnancy. It is mainly during this time that some medicines are known to cause birth defects.

There is no evidence that pregnant women taking cetirizine have a higher chance of having a baby with a birth defect. However, because fewer than 500 pregnancies where the mother took cetirizine during the first trimester have been studied, further research is required to confirm these findings.

Can taking cetirizine in pregnancy cause miscarriage?

The likelihood of miscarriage has been assessed in around 430 women taking cetirizine in early pregnancy. Although the studies do not raise concern that cetirizine causes miscarriage, ongoing research is ideally required to confirm this.

Can taking cetirizine in pregnancy cause preterm birth, or my baby to be small at birth (low birth weight)?

No links between cetirizine use in pregnancy and pre-term birth (before 37 weeks of pregnancy) or low birth weight (<2500 g) were found in any of the three studies that investigated these outcomes.

Can taking cetirizine in pregnancy cause stillbirth?

There is no known link between cetirizine use in pregnancy and stillbirth. However, the chance of stillbirth has been investigated in fewer than 200 pregnant women taking cetirizine, so ongoing research is required.

Can taking cetirizine in pregnancy cause learning and behavioural problems in the child?

A baby’s brain continues to develop right up until the end of pregnancy. It is therefore possible that taking certain medicines at any stage of pregnancy could have a lasting effect on a child’s learning or behaviour.

No studies have assessed the learning and behaviour of children exposed in the womb to cetirizine.

Will my baby need extra monitoring?

Most women will be offered a scan at around 20 weeks of pregnancy to look for birth defects as part of their routine antenatal care. Taking cetirizine in pregnancy would not normally require extra monitoring of your baby.

Are there any risks to my baby if the father has taken cetirizine?

We would not expect any increased risk to your baby if the father took cetirizine before or around the time you became pregnant.

Who can I talk to if I have questions?

If you have any questions regarding the information in this leaflet please discuss them with your health care provider. They can access more detailed medical and scientific information from www.uktis.org.

How can I help to improve drug safety information for pregnant women in the future?

Our online reporting system (MyBump Portal) allows women who are currently pregnant to create a secure record of their pregnancy, collected through a series of questionnaires. You will be asked to enter information about your health, whether or not you take any medicines, your pregnancy outcome and your child's development. You can update your details at any time during pregnancy or afterwards. This information will help us better understand how medicines affect the health of pregnant women and their babies. Please visit the MyBump Portal to register.

General information
Sadly, miscarriage and birth defects can occur in any pregnancy.

Miscarriage occurs in about 1 in every 5 pregnancies, and 1 in every 40 babies are born with a birth defect. This is called the ‘background risk’ and happens whether medication is taken or not.

Most medicines cross the placenta and reach the baby. For many medications this is not a problem. However, some medicines can affect a baby’s growth and development.

If you take regular medication and are planning to conceive, you should discuss whether your medicine is safe to continue with your doctor/health care team before becoming pregnant. If you have an unplanned pregnancy while taking a medicine, you should tell your doctor as soon as possible.

If a new medicine is suggested for you during pregnancy, please make sure that the person prescribing it knows that you are pregnant. If you have any concerns about a medicine, you can check with your doctor, midwife or pharmacist.

Our Bumps information leaflets provide information about the effects of medicines in pregnancy so that you can decide, together with your healthcare provider, what is best for you and your baby.