bumps - best use of medicine in pregnancy


(Date: July 2014. Version: 2)

This factsheet has been written for members of the public by the UK Teratology Information Service (UKTIS). UKTIS is a not-for-profit organisation funded by Public Health England on behalf of UK Health Departments. UKTIS has been providing scientific information to health care providers since 1983 on the effects that medicines, recreational drugs and chemicals may have on the developing baby during pregnancy.

What is it?

Fexofenadine (Telfast®) is a non-sedating antihistamine which is used to treat hay fever, skin allergies and other allergic symptoms, and does not cause drowsiness.

Is it safe to take fexofenadine in pregnancy?

This leaflet summarises the scientific studies relating to the effects of fexofenadine on a baby in the womb. It is advisable to consider this information before taking fexofenadine if you are pregnant.

There are very few studies of women who specifically took fexofenadine in pregnancy. There are a number of studies of pregnant women who used any antihistamine, or antihistamines chemically related to fexofenadine. However, because each antihistamine might affect a baby in the womb differently, we do not know whether the findings from these studies apply to women specifically taking fexofenadine. Fexofenadine is therefore not currently recommended for use in pregnancy unless other antihistamines for which there is more information have been tried first.

When deciding whether or not to take fexofenadine during pregnancy it is important to weigh up how necessary fexofenadine is to your health against the possible risks to you or your baby, some of which will depend on how many weeks pregnant you are. Your doctor will be able to advise you about this and is the best person to help you decide what is right for you and your baby.

What if I have already taken fexofenadine during pregnancy?

If you have taken or are taking any medicines it is always a good idea to let your doctor know that you are pregnant so that you can decide together whether you still need the medicines that you are on and, if so, to make sure that you are taking the lowest dose that works and only for as long as you need to.

Can taking fexofenadine 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.

One study looked at whether children with heart defects, or one of any of over 20 other specific birth defects, were more likely to have been exposed in the womb to fexofenadine than children without birth defects. The study found no link with fexofenadine use during pregnancy.

Other studies that investigated groups of pregnant women taking any antihistamine (a few of whom took fexofenadine or the related antihistamine terfenadine) also found no increased risk of birth defects in the baby. More research is needed to specifically assess fexofenadine use in pregnancy.

Can taking fexofenadine in pregnancy cause miscarriage?

The only study which has investigated this risk found that miscarriages were no more common among the 30 women in the study who took fexofenadine during the first trimester of pregnancy than in pregnant women generally.

The only study on the related antihistamine terfenadine also found no increase in the rate of miscarriage.

One study has investigated the risk of miscarriage in a group of pregnant women who were taking any antihistamine. This also showed no increased risk of miscarriage.

Because miscarriage rates have been studied in very few women specifically taking fexofenadine during early pregnancy, more research into this subject is required.

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

No studies have investigated whether preterm birth (before 37 weeks of pregnancy) or having a low birth weight baby (<2500g) is more common in women who took fexofenadine during pregnancy.

One study of pregnant women taking the related antihistamine terfenadine did not find any links with preterm birth or low birth weight in the baby.

Two studies of women taking any antihistamine in pregnancy also found no link with either preterm birth or low birth weight. However, we do not know how these findings relate to women taking fexofenadine and more information therefore needs to be collected from women who are taking fexofenadine in pregnancy.

Can taking fexofenadine in pregnancy cause stillbirth?

No studies have investigated the occurrence of stillbirth in women who took fexofenadine during pregnancy.

One study has investigated pregnant women taking the related antihistamine terfenadine during pregnancy and did not find a link with stillbirth. However, we do not know whether fexofenadine and terfenadine affect a baby in the womb differently and more research is therefore required to answer this question.

Can taking fexofenadine 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.

There is no known link between taking fexofenadine in pregnancy and learning or behavioural problems (such as ADHD or autism spectrum disorder) in the child later on in life. There are, however, no scientific studies that have specifically investigated a link with these problems.

One study has assessed children who had been exposed in the womb to the related antihistamine terfenadine. Their development at one year of age was similar to that of children whose mothers had not taken terfenadine in pregnancy.

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 fexofenadine in pregnancy would not normally require extra monitoring of your baby.  

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

We would not expect any increased risk to your baby if the father took fexofenadine 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.  

General information 

Up to 1 out of every 5 pregnancies ends in a miscarriage, and 1 in 40 babies are born with a birth defect. These are referred to as the background population risks.  They describe the chance of these events happening for any pregnancy before taking factors such as the mother’s health during pregnancy, her lifestyle, medicines she takes and the genetic make up of her and the baby’s father into account.

Medicines use in pregnancy

Most medicines used by the mother will cross the placenta and reach the baby. Sometimes this may have beneficial effects for the baby.  There are, however, some medicines that can harm a baby’s normal development.  How a medicine affects a baby may depend on the stage of pregnancy when the medicine is taken. If you are on regular medication you should discuss these effects with your doctor/health care team before becoming pregnant.

If a new medicine is suggested for you during pregnancy, please ensure the doctor or health care professional treating you is aware of your pregnancy.

When deciding whether or not to use a medicine in pregnancy you need to weigh up how the medicine might improve your and/or your unborn baby’s health against any possible problems that the drug may cause. Our bumps leaflets are written to provide you with a summary of what is known about use of a specific medicine in pregnancy so that you can decide together with your health care provider what is best for you and your baby.   

Every pregnancy is unique. The decision to start, stop, continue or change a prescribed medicine before or during pregnancy should be made in consultation with your health care provider. It is very helpful if you can record all your medication taken in pregnancy in your hand held maternity records.



Disclaimer: This information is not intended to replace the individual care and advice of your health care provider. New information is continually becoming available. Whilst every effort will be made to ensure that this information is accurate and up to date at the time of publication, we cannot cover every eventuality and the information providers cannot be held responsible for any adverse outcomes following decisions made on the basis of this information. We strongly advise that printouts should NOT be kept for any length of time, or for “future reference” as they can rapidly become out of date.

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