Advising on medicines during breastfeeding

Benefits of breastfeeding

Breastfeeding provides nutrition tailored to the individual infant’s needs. It also provides immunoglobulins and other bioactive components which contribute to the establishment of a healthy infant microbiome, helping to reduce infections. There is overwhelming evidence of the benefits of breastfeeding to the infant (for example reduced risk of sudden infant death syndrome, diabetes, and asthma). And to the mother (for example reduced risk of breast cancer, post-partum depression, and cardiovascular disease).

The WHO recommends exclusive breastfeeding for the first 6 months of life. Complementary foods can then be introduced, while continuing breastfeeding for up to 2 years of age or beyond.

Advising against breastfeeding carries risk

Stopping breastfeeding when a medicine is prescribed is therefore not a “no-risk” option for either the mother or the infant. Equally, if a medicine is required, this should not be denied due to a perceived unmanageable risk.

The benefits of breastfeeding should always be part of any risk assessment when managing medicine use during breastfeeding.

Developing your advice

Once you have completed a risk assessment of the medicine(s) in breastfeeding (SPS page), you are ready to provide advice. The overall aim should be to allow the mother to continue breastfeeding where possible, whilst taking the most appropriate treatment.

In the majority of cases this will be possible, particularly if you have based your risk assessment on suitable information sources (SPS page). However in some cases, where medicines cannot be continued as normal whilst breastfeeding, you may need to suggest different options.

Choice of medicine

Risks to the infant can be reduced by choosing options which are more suitable for breastfeeding. However, it is important to make sure that the medicine is appropriate and effective for the condition being treated, with safety in breastfeeding a secondary consideration.

If the medicine has not yet been started, it is easier to suggest a more suitable alternative. If treatment is already established, switching to an alternative may not be a suitable clinical option and may also not be practical.

Simplify the medication

Avoid unnecessary medicine use, including self-medication and complementary therapies. In general, the less medicines that are being taken, the less risk to the infant. Consider whether non-medicinal options could be used instead.

If the medicines have been taken during pregnancy, review these before delivery and consider whether the medicine could be stopped.

It is also good practice to be reviewing medicines suitability for breastfeeding before the birth so that there is time to make an informed choice. Suitability in breastfeeding is usually only considered after the birth, which is often an unsettled time.

Offer alternatives where suitable

In some cases, a different medicine may be a more suitable choice or have more evidence for its use during breastfeeding.

Different routes of administration can also be considered. For example topical or inhaled routes give lower levels in the breast milk and therefore may be more suitable than systemic routes of administration.

However, always ensure changes in therapy or administration route are suitable for the patient’s clinical condition.

Medicine properties

The properties and pharmacokinetics of the medicine can be used to assess how likely a medicine may pass into breast milk. For example, high protein binding, volume of distribution, and molecular weight values are all favourable properties which theoretically reduce passage into breast milk.

Medicines with a long half-life can increase the risk of accumulation in the infant and therefore increase the risk of side effects. Neonates (and particularly premature infants) are at greater risk because of immature excretory functions.

If the medicine has low oral bioavailability, it is unlikely to be absorbed in significant amounts by the infant through breast milk.

Medicines used directly in infants

Medicines which are used therapeutically in infants provide reassurance for their compatibility in breastfeeding. The concentrations they are being exposed to via breast milk are far less than if they were given the medicine directly.

However the risk-benefit balance of an infant being exposed to a medicine they need is different to being exposed to a medicine they do not need (via breast milk).

Further considerations

Multiple medication regimens may pose an increased risk especially when side effects such as drowsiness are additive.

Avoid new medicines if a therapeutically equivalent alternative that has been more widely used, and if clinically appropriate.

Avoid use of medicines known to cause serious toxicity in adults or children.

Timing of feeds

Seek further advice from the UK Drugs in Lactation Advisory Service, our specialist breastfeeding medicines advice service (SPS page) before suggesting either of the following approaches to reduce infant exposure:

• giving the dose immediately after the infant has been fed with the aim of avoiding feeding at peak milk concentrations
• withholding breastfeeding until after a suitable washout period of the medicine. This is most appropriate for short courses of a hazardous medicine

Both options rely on knowledge of pharmacokinetic data, which may be unreliable or not readily available. In addition they are often impractical, especially where young infants are feeding very frequently on demand.

Withholding breastfeeding for a period of time also requires support to maintain lactation during the abstinence period, for example expressing breast milk .

Monitoring the infant

It’s always important to advise on what to look out for in the infant to indicate if they’re experiencing an effect from the medicine through breastmilk. This is one of the key risk-reducing methods to manage medicine exposure.

Monitoring the infant will quickly pick up any potential issues but usually further investigation is required before the cause can be attributed to the medicine.

The following can be helpful:

• advise that infant side effects are rare. Monitoring is usually used as a precaution
• monitoring is of increased importance in younger, exclusively breastfed infants, premature infants, and those exposed to multiple medicines
• give practical tips and think about who you are advising. For example:
  • rather than telling parents to simply monitor for drowsiness, advise them to make sure the infant is waking up to feed, or isn’t sleeping for longer, or more often, than expected
  • a parent won’t be able to monitor for hypotension, but they could monitor for symptoms such as lethargy and pallor
• give general advice to make sure the infant is feeding well, putting on weight, and achieving developmental milestones

You can find information on what to monitor for individual medicines by searching our medicines specific advice during breastfeeding (SPS page).

Communication

Include all those involved with caring for the infant in the discussion, for example the partner or other members of the family. You may also need to liaise with other healthcare professionals involved in their care.

Expert advice

If there is any doubt about the safety of a medicine or combination of medicines in breastfeeding, or if you are thinking of advising against breastfeeding. Seek further advice from our Medicines Advice service (SPS page) or the UK Drugs in Lactation Advisory Service (UKDILAS), our specialist breastfeeding medicines advice service (SPS page)

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