Breastfeeding: Reducing risk

Last updated: Monday, April 08, 2019

Consider the following points when advising on medicine use in a breastfeeding mother:

  • If the drug is not essential it should be avoided, or a non-pharmacological approach used instead.

  • There may be alternative drugs that are safer to use. However, choice of drug should be based primarily on suitability for the patient and their condition, and then compatibility with breastfeeding assessed.

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  • Frequency of breastfeeding varies a lot according to age. For example, a newborn baby might feed every hour, whereas a one-year-old infant may be feeding only twice a day. This means it’s important to ask about the feeding regimen before suggesting how the administration of medicines might fit in. For example, it would be pointless suggesting that a mother takes a long-acting medicine at bedtime to reduce infant exposure, if she feeds him throughout the night. 

  • Similarly, breastfeeding immediately before a dose, in an attempt to reduce exposure to peak plasma levels, might not be a practical option.

  • For a very short course of treatment (less than 48 hours) breastfeeding could be interrupted temporarily, but longer interruption can make resumption difficult. This option should be avoided if at all possible.

  • As in any situation where the risk of side effects must be minimised: avoid multiple drugs with similar potential adverse reactions; use minimum doses and dosage forms that limit systemic exposure (e.g. inhalers); avoid new drugs and medicines with long half-lives if possible.


The UK Drugs In Lactation Advisory Service (UKDILAS) is an NHS specialist centre for medicine use in breastfeeding mothers. It offers guidance online or you can ring the service for advice.