using contrast agents during breastfeeding

UK guidance states (1):

• although there is limited published evidence about the use of amidotrizoate, barium, iodinated, and gadolinium-based contrast agents in breastfeeding, significant transfer into breast milk is not expected due to the properties of these agents
  • the poor oral bioavailability of these agents means that they are unlikely to be absorbed from breast milk in clinically significant amounts, and therefore unlikely to cause side effects in breastfed infants

The Royal College of Radiologists (RCR) and the Society of Radiographers (SoR) state (2):

• "..it is the view of both the RCR and the SoR that patients who wish to continue breast feeding after being administered with contrast agent – usually given in advance of a CT or MRI scan – should be able to do so as there is no evidence of risk to the baby/child. If you have any concerns please, speak with your radiographer or radiologist.."

Reference:

1. NHS Specialist Pharmacy Service (April 2025). Using contrast agents during breastfeeding
2. Royal College of Radiologists (RCR) and the Society of Radiographers (SoR) statement on patients who are breastfeeding who require a CT or MRI with contrast (January 2022)