Nortriptyline

What are they?

Tricyclic antidepressants (TCAs) include the medicines amitriptyline, clomipramine, dosulepin (Thaden®), doxepin (Sinepin®), imipramine, lofepramine, nortriptyline and trimipramine.  They are used to treat depression, anxiety, and certain types of nerve pain.

There is a separate bump leaflet on Use of amitriptyline in pregnancy.

Is it safe to take a TCA in pregnancy?

When deciding whether or not to take a tricyclic antidepressant during pregnancy it is important to weigh up how necessary this treatment 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. Remaining well is particularly important during pregnancy and whilst caring for a baby. For some pregnant women treatment with a TCA may therefore be considered necessary, for example where no other treatment is available or suitable.

This leaflet summarises the scientific studies relating to the effects of tricyclic antidepressants on a baby in the womb. It is advisable to consider this information if you are taking a TCA and are pregnant or could become pregnant in the future.

Your doctor is the best person to help you decide what is right for you and your baby.

What if I have already taken a TCA during pregnancy?

If you have taken 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 to make sure that you are taking the lowest dose that works.

It is very important that you do not suddenly stop taking a tricyclic antidepressant as this could be dangerous to you, and to your baby if you are already pregnant. Do not make any change to your medication without first talking to your doctor.

Can taking a TCA in pregnancy cause birth defects in my 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 mixed scientific evidence about whether taking a TCA during the first trimester of pregnancy may increase the chance of having a baby with a birth defect.

Studies of almost 10,000 pregnant women taking any TCA in the first trimester of pregnancy did not show overall that this increases the chance of the baby having any birth defect, or of heart defects specifically. However, a study of around 1,000 women taking clomipramine during early pregnancy found possible links with heart defects in the baby. Much larger studies need to be carried out to confirm these findings and future research should also take into account the possible effects of underlying illness in the mother on the chance of birth defects in the baby. There is currently no information on the possible effects of use in pregnancy of other specific TCAs.

Can taking a TCA in pregnancy cause miscarriage?

Three studies have investigated a possible link between miscarriage and use of any TCA in pregnancy. Two studies found a possible link while the third did not. It is unclear whether any possible link may be due to an effect of TCAs themselves, or whether underlying maternal ill health may also contribute. Further well-designed studies are required to answer this question, and to assess the chance of miscarriage in women taking specific TCAs.

Can taking a TCA in pregnancy cause stillbirth?

No studies have specifically assessed the chance of stillbirth following use of TCAs in pregnancy. However, a single study of around 4,000 pregnant women taking any TCA showed that their babies did not have a higher chance of dying either just before or just after delivery than babies born to women not taking TCAs. Research into the chance of stillbirth and the possible effects of specific TCAs is required.

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

Six studies of women taking any TCA in pregnancy do not show overall that causes low birth weight in the baby. However, a number of studies have found a possible link between use of TCAs in pregnancy and preterm birth. It is unclear whether this may be due to an effect of TCAs themselves, underlying maternal ill health, or a combination of these factors. More research is required to answer these questions, and to investigate the potential effects of specific TCAs.

Can taking a TCA in pregnancy cause other health problems in the child?

Withdrawal symptoms at birth (‘neonatal withdrawal’)
Withdrawal symptoms are thought to occur as the newborn baby’s body has to adapt to no longer getting certain types of medicines through the placenta. Exposure to TCAs during pregnancy can cause neonatal withdrawal. Therefore, close monitoring of your baby for a few days after birth may be advised if you have taken a TCA regularly in the weeks before delivery.

Learning and behavioural problems
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.

Small studies of general learning and development in children up to the age of 7 years who were exposed to a TCA in the womb have not shown any adverse effects. However, a single study found a possible link between TCA exposure in the womb and attention-deficit hyperactivity disorder in children, which requires confirmation with further research. Two studies of the chance of autism following exposure to a TCA in the womb produced different findings. While one found no increased chance of autism in exposed children, a second showed an increase, but found that this may be linked to depression in the mother rather than an effect of a specific medicine. A single study of children exposed to specific TCAs found no links between childhood autism and exposure to nortriptyline, but found a possible link with clomipramine exposure.

Further well-designed studies that take into account the possible effects of the mother’s underlying ill health are required to determine whether exposure to TCAs in the womb can affect learning and behaviour.

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 a TCA in pregnancy would not be expected to cause problems that require extra monitoring of your baby.

If you have taken a TCA around the time of delivery your baby may require extra monitoring after birth because of the possible risk of neonatal withdrawal symptoms.

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

We would not expect any increased risk to your baby if the father took a TCA 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 healthcare provider. They can access more detailed medical and scientific information from www.uktis.org.