Most medicines pass into breast milk in small amounts, and the infant dose is usually a small fraction of the maternal dose. The risk is higher for premature or newborn infants, drugs with long half-lives or active metabolites, and drugs that are poorly cleared by the infant.
Prefer drugs with established breastfeeding data, shorter half-lives and lower oral bioavailability. Where a choice exists, a single agent is safer than several. Advise the mother what to watch for in the infant, such as drowsiness, poor feeding or rash.
- Prefer medicines with established breastfeeding data and short half-lives
- Take extra care with preterm and newborn infants
- Limit the number of drugs where possible
- Tell the mother which infant signs to watch for
- Use a dedicated drugs-in-lactation reference rather than the general product leaflet
Why it matters
Unnecessary weaning often follows cautious leaflet wording rather than evidence.
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