Levocetirizine Safety in Breastfeeding
Levocetirizine is not recommended during breastfeeding according to the FDA drug label, though research evidence suggests minimal infant exposure with relative infant doses well below safety thresholds. 1
FDA Labeling Position
- The FDA-approved product labeling explicitly states that levocetirizine is "not recommended" if breastfeeding 1
- This represents the most authoritative regulatory guidance and should frame clinical decision-making 1
Research Evidence on Antihistamine Safety
Despite the FDA's conservative stance, published research provides additional context:
- All antihistamines are considered safe during breastfeeding according to a 2010 Canadian Family Physician review, as minimal amounts are excreted in breast milk and would not cause adverse effects on breastfeeding infants 2
- A 2022 systematic review found that relative infant doses for all studied antihistamines were below 5%, ranging from 0.3% to 4.5%, which is well below the generally accepted 10% safety threshold 3
- The same systematic review noted that cetirizine (the racemic mixture containing levocetirizine) had minimal breast milk transfer 3
Clinical Caveat
- Most antihistamine product labels in both the EU and United States report lack of evidence and recommend avoiding use during breastfeeding, despite the reassuring pharmacokinetic data 3
- This discrepancy reflects the knowledge gap on antihistamines and lactation, with insufficient human studies to definitively establish safety 3
Practical Recommendation
Given the FDA's explicit "not recommended" designation, alternative antihistamines with more established breastfeeding safety profiles should be prioritized. 1 If levocetirizine is deemed necessary, this decision should involve informed discussion about the regulatory position versus the limited but reassuring research data on antihistamine class effects. 2, 3