Cetirizine Safety in Lactating Mothers
Cetirizine is safe to use during breastfeeding, with minimal transfer into breast milk and no significant risk to the breastfed infant.
Evidence Supporting Safety
The most recent and highest quality evidence demonstrates that cetirizine transfer into breast milk is minimal and poses negligible risk:
The relative infant dose (RID) of cetirizine is extremely low at 1.77-1.99%, well below the 10% safety threshold used to determine compatibility with breastfeeding 1, 2.
Even at peak maternal concentrations (Cmax), the highest predicted RID reaches only 3.36%, which remains well within safe limits 2.
No adverse effects have been reported in breastfed infants whose mothers used cetirizine 1.
Population pharmacokinetic modeling confirms that infant exposure via breast milk is low enough to support that cetirizine is compatible with breastfeeding 2.
Guideline Recommendations
While there is some divergence in official guidance, the most recent evidence supersedes older cautions:
Recent guidelines acknowledge that while older recommendations advised caution with antihistamines during lactation, newer research specifically on cetirizine provides reassurance about its safety 3.
The FDA label states cetirizine is "not recommended" during breastfeeding, but this reflects insufficient historical data rather than evidence of harm 4.
This FDA position is now contradicted by multiple recent studies demonstrating safety 1, 2.
Important Caveats
Renal impairment requires dose adjustment:
Avoid cetirizine entirely if the mother has severe renal impairment 3.
Reduce the cetirizine dose by half if the mother has moderate renal impairment 3.
Clinical Bottom Line
The discrepancy between FDA labeling and current research reflects the lag in regulatory updates. The preponderance of recent evidence (2021-2025) clearly demonstrates that cetirizine can be safely used during breastfeeding without interruption, given the minimal milk transfer and absence of reported infant adverse effects 1, 2.