Cetirizine Safety During Lactation
Cetirizine is considered compatible with breastfeeding due to minimal transfer into breast milk and low infant exposure. 1, 2, 3
Evidence on Cetirizine in Breastfeeding
- The FDA label for cetirizine states "not recommended if breast-feeding" 4, however this is inconsistent with more recent and detailed research evidence.
- Recent human lactation studies demonstrate that cetirizine transfers into breast milk in minimal amounts, with a relative infant dose (RID) of only 1.9% 3, well below the generally accepted safety threshold of 10%.
- The maximum RID observed was 3.36% at peak concentration, still considered very low 1.
- No adverse effects have been reported in breastfed infants whose mothers were taking cetirizine 2.
Quantified Exposure Data
- Mean maximum cetirizine concentration in breast milk is approximately 41.0 μg/L 3.
- The estimated absolute infant dose is only 2.5 μg/kg/day 3.
- Cetirizine reaches maximum concentration in breast milk about 2.4 hours after maternal intake and has a half-life in milk of approximately 7 hours 3.
Clinical Considerations
- While the British Journal of Dermatology guidelines (2007) recommend caution with antihistamines during lactation 5, more recent research specifically on cetirizine provides reassurance about its safety.
- All antihistamines are generally considered safe during breastfeeding as minimal amounts are excreted in breast milk 6.
- Cetirizine is preferable to first-generation (sedating) antihistamines during breastfeeding, as the older antihistamines may cause sedation in both mother and potentially the infant 6.
Special Considerations
- If the mother has severe renal impairment (creatinine clearance <10 mL/min), cetirizine should be avoided 5.
- For moderate renal impairment, the dose of cetirizine should be halved 5.
- Monitor the infant for unusual drowsiness or feeding difficulties, although these effects are unlikely given the minimal transfer into breast milk 1, 2.
Conclusion
Based on the most recent and highest quality evidence, cetirizine can be safely used by lactating mothers with minimal risk to the breastfeeding infant. The extremely low relative infant dose of less than 2% indicates that the amount transferred through breast milk is unlikely to cause any adverse effects in the infant.