Antacids, alginates, H2-receptor antagonists or proton pump inhibitors can be used during breastfeeding. Recommendations are for full term and healthy infants.

General considerations

It is important to complete an individual risk assessment for your patient and to apply the principles of prescribing in breastfeeding when looking at the available information and making treatment decisions.


We provide a summary of the recommendations by mechanism of action.

Antacid and alginate preparations

There is extensive experience of use of antacids during breastfeeding and they are considered first-line options for managing heartburn or dyspepsia.

Alginates and simeticone are also considered acceptable for use during breastfeeding.

Histamine (H2)-receptor antagonists

Any H2-receptor antagonist can be used during breastfeeding. Famotidine or nizatidine are preferred as smaller amounts pass into breast milk. Cimetidine is least preferred due to higher levels in breast milk and the potential for drug interactions.

Proton pump inhibitors (PPIs)

Any PPI can be used during breastfeeding, however omeprazole and pantoprazole are the PPIs of choice as they are excreted into breast milk in very small amounts and have evidence to support their use. Any PPI that passes into breast milk is likely to be degraded in the infant’s gastrointestinal tract.

Clinical considerations

Lifestyle and dietary modifications to manage heartburn and dyspepsia during breastfeeding should always be tried first. If these measures fail to manage symptoms then antacids or alginates can be tried followed by H2-receptor antagonists or PPIs if required.

Antacids are usually aluminium, calcium, magnesium or sodium salts and are intended for short-term symptom control.  These are all found naturally in breast milk.  Additional intake of these is unlikely to affect levels in breast milk.

Antacids, along with alginates and simethicone, have poor oral bioavailability which will limit the amount ingested by the breastfed infant.

Effect on breast milk production

Use of H2-receptor antagonists or PPIs may lead to an increase in prolactin levels which can cause galactorrhoea in non-breastfeeding patients. The clinical significance of this on milk production in those who are breastfeeding is unknown. However, where breastfeeding is established this is unlikely to have a significant effect.

Specific recommendations

The following recommendations have been grouped by mechanism of action.

Antacids and alginates

H2-receptor antagonists

Proton pump inhibitors

Patient Information

The NHS website provides advice for patients on the use of specific medicines in breastfeeding.

Contact us

Get in touch with the UK Drugs In Lactation Advisory Service (UKDILAS), our specialist breastfeeding medicines advice service if you need support in the following situations:

  • you need further advice
  • the medicine in question is not included here
  • the infant is unwell or premature
  • multiple medicines are being taken

About our recommendations

Recommendations are based on published evidence where available. However, evidence is generally very poor and limited, and can require professional interpretation. Assessments are often based on reviewing case reports which can be conflicting and lack detail.

If there is no published clinical evidence, assessments are based on: pharmacodynamic and pharmacokinetic principles, extrapolation from similar drugs, risk assessment of normal clinical use, expert advice, and unpublished data. Simulated data is now increasingly being used due to the ethical difficulties around gathering good quality evidence in this area.


Full referencing is available on request.

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