Proton pump inhibitors (PPIs)

Date: July 2024, Version 1.0

What are they?

Proton pump inhibitors (PPIs) reduce the production of stomach acid and are used to treat indigestion, acid reflux, and stomach ulcers. PPIs available in the UK include omeprazole [Losec®, Mezzopram®], lansoprazole [Zoton®], esomeprazole [Emozul®, Nexium®], pantoprazole [Protium®], and rabeprazole [Pariet®].


What are the benefits of taking a PPI?

Indigestion and acid reflux are common in pregnancy and can cause pain and discomfort. Use of a PPI can greatly improve these symptoms.

PPIs can also help stomach ulcers to heal and prevent serious complications.

Omeprazole is the PPI that is preferred for use in pregnancy as there is more information about its safety. However, other PPIs can also be used if advised by a doctor.


Are there any risks of taking a PPI in pregnancy?

Omeprazole is commonly used in pregnancy. There is no good evidence that omeprazole or other PPIs are linked to miscarriage, birth defects, stillbirth, preterm delivery, or low infant birth weight.

Some (but not all) studies have shown possible links between use of medicines in pregnancy that reduce stomach acid and allergy and asthma in children. Further research is required to determine whether there is a true link. Reassuringly, the studies all showed that the vast majority of exposed children did not have allergies or asthma.


Are there any alternatives to taking a PPI?

Possibly. Some women with indigestion and acid reflux find that their symptoms can be improved with lifestyle measures, such as avoiding fatty foods, ensuring that they do not gain too much weight, not smoking, and sleeping with the head of their bed raised. Other medicines such as antacids or alginates (e.g. Gaviscon) can also be tried before a PPI is used.

PPIs are usually the medicine of choice to treat a stomach ulcer in pregnancy. This is because there is less safety information about the drugs which might be used instead. If you have any concerns you can arrange to speak to your GP or specialist, but you should not stop taking a PPI unless you doctor has asked you to do this.

No treatment

What if I prefer not to take medicines to treat indigestion, acid reflux, or stomach ulcers?

Indigestion and acid reflux are uncomfortable and sometimes painful but when experienced short-term in pregnancy generally do not pose a significant health risk. Therefore, some pregnant women may choose not to use treatments. However, if indigestion and acid reflux are affecting quality of life (such as causing pain, affecting sleep etc.) then the benefits of treatment may outweigh any worries about hypothetical risks. Your doctor or midwife will be happy to discuss any concerns you may have. 

Medicines prescribed to treat stomach ulcers should not be stopped or changed unless upon the advice of a GP or specialist.

Will my baby need extra monitoring?

Most women will be offered a scan at around 20 weeks of pregnancy to check their baby’s wellbeing as part of their routine antenatal care. No additional monitoring is required following use of a PPI.

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

We would not expect any increased risk to your baby if the father takes a PPI.

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

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.