Cetirizine Use in Lactating Women
Cetirizine is safe and compatible with breastfeeding, with minimal infant exposure (relative infant dose of approximately 1.77-1.99%) and no reported adverse effects in breastfed infants. 1, 2
Evidence-Based Safety Profile
The most recent and highest quality evidence demonstrates excellent safety:
- Population pharmacokinetic modeling from 2025 found a mean relative infant dose (RID) of 1.99%, with the highest RID being only 3.36% at peak maternal concentrations 1
- This RID is well below the 10% threshold generally considered safe for breastfeeding 1
- A 2021 study confirmed minimal transfer into breast milk with an RID of 1.77% at 24 hours, with no adverse effects reported in infants 2
Clinical Recommendations
Cetirizine can be used during lactation without interrupting breastfeeding. The evidence supports:
- All antihistamines, including cetirizine, are considered safe during breastfeeding as minimal amounts are excreted in breast milk 3
- Recent guidelines acknowledge that while older recommendations advised caution, current research on cetirizine specifically provides reassurance about its safety 4
Important Caveats
Maternal renal function must be considered:
- Avoid cetirizine if the mother has severe renal impairment 4
- Reduce the dose by 50% if the mother has moderate renal impairment 4
Guideline Discordance
Note that the FDA label states cetirizine is "not recommended" during breastfeeding 5, but this recommendation predates the robust pharmacokinetic studies from 2021-2025 that demonstrate minimal infant exposure and excellent safety 1, 2. The most recent high-quality research should guide clinical practice in this case.