Questions to ask when giving advice on medicines and breastfeeding

Importance of the risk assessment

Medicines might have been taken through pregnancy or may be newly prescribed while breastfeeding. Sometimes there is a need to restart a medicine which had been stopped or changed due to pregnancy. The ideal scenario is to complete a risk assessment before the infant is born, or before the medicine is started, so a plan is already in place.

Challenges of the risk assessment

Assessing risk is particularly challenging because of the lack of information about:

• excretion of medicines into breast milk
• how much of this the infant might absorb
• if infant side effects have been reported

The age of the infant, and whether they were born premature, must be also be considered. The pharmacokinetics, and the amount of medicine being exposed to, will be very different for a newborn or premature infant compared with an older child.

The overall aim should be to allow breastfeeding to continue where possible. Advising to stop breastfeeding is not a ‘no-risk’ option as it denies the infant and mother the benefits of breastfeeding.

Importance of asking questions

Full details about the mother, the infant and the medicine are needed to inform the risk assessment for each individual situation.

Full details about the breastfeeding patient, the infant and the medicines are needed to inform the risk assessment for each individual situation.

It cannot be assumed that a medicine assessed for use during pregnancy will have the same risk during breastfeeding. This is because the infant now has to rely on its own excretion and metabolism, rather than the maternal systems through pregnancy. A risk assessment for the use of a medicine in breastfeeding is therefore still required, even if the medicine was taken throughout pregnancy.

Most medicines will be excreted into breast milk to some extent. But in most cases breastfeeding can continue whilst taking the medicines. Decisions can be informed by obtaining sufficient information to make a good risk assessment.

Informing the risk assessment

It is important to consider the risk of the medicine exposure to the infant through breastmilk. This needs to be balanced against the risks from either not treating the condition or from discontinuing breastfeeding.

The following steps are useful to structure a risk assessment:

If you need further advice

If you can’t find any information, seek further advice from our Medicines Advice contact details (SPS page). If your clinical scenario is complex, contact the UK Drugs in Lactation Advisory Service (UKDILAS), our Breastfeeding Medicines Advice service (SPS page).

Ensure you have gathered as much information as possible by completing steps 1 to 4 before contacting the service so our team can help you further.

Types of complex enquiry UKDILAS can help with include:

• risk assessment for medicines while breastfeeding premature and health compromised infants
• breastfeeding with multiple medicines or complex treatment plans
• overdosing and accidental ingestion
• excretion of medicines, diagnostic agents and chemicals into breast milk
• effects of medicines on milk production, including the enhancement and suppression of lactation

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