Is loratadine (Claritin) safe to use during pregnancy?

Is Loratadine Safe in Pregnancy?

Yes, loratadine is safe to use during pregnancy and is recommended as a first-line antihistamine choice, including during the first trimester. 1, 2

Guideline-Based Recommendations

Loratadine and cetirizine should be the first choice when antihistamine therapy is necessary during pregnancy, including the first trimester. 2 Multiple major allergy and respiratory societies recommend these two agents as preferred options based on extensive safety data. 1, 2

FDA Classification and Safety Profile

• Loratadine is classified as FDA Pregnancy Category B, meaning no evidence of fetal harm exists in available studies. 2
• The FDA drug label states: "If pregnant or breast-feeding, ask a health professional before use," which is standard precautionary language rather than a contraindication. 3
• Large birth registries, case-control studies, and cohort studies confirm the safety of second-generation antihistamines like loratadine during the first trimester. 1

Supporting Research Evidence

Robust Human Data

• Loratadine is the most studied second-generation antihistamine in pregnancy, with a total patient cohort of 2,147 women exposed. 4 This represents substantially more data than other newer antihistamines.
• A multicenter prospective study of 161 loratadine-exposed pregnancies found no increased risk for major malformations (5 malformations in exposed group vs. 6 in controls, P=0.9). 5
• Another prospective controlled cohort study of 210 pregnancies exposed to loratadine (77.9% in first trimester) showed no difference in congenital anomaly rates compared to controls [2.3% vs. 3.0%, RR 0.77,95% CI 0.27-2.19]. 6

First Trimester Safety

The first trimester is the most critical period when organogenesis occurs and medication-related congenital malformations are most likely. 1 Despite this vulnerability window, loratadine has demonstrated safety even with first-trimester exposure. 6

• Among first-trimester exposures specifically, the malformation rate was 0.8% for loratadine versus 3.0% for controls (P=0.152). 6
• Second-generation antihistamines in general do not show a significant increase in congenital malformations when used during the first trimester. 1

Clinical Decision-Making Algorithm

When to Use Loratadine

1. For moderate to severe allergic rhinitis symptoms requiring pharmacologic treatment during pregnancy, start with loratadine or cetirizine. 1, 2
2. Choose between loratadine and cetirizine based on prior response, side effect profile, and cost. 2
3. If the patient has already been using loratadine successfully before pregnancy, continue it. 2

Combination Therapy for Severe Symptoms

• Combine loratadine with intranasal corticosteroids (particularly budesonide) for moderate-severe symptoms. 2 Intranasal corticosteroids have strong safety data and minimal systemic absorption. 1

Agents to Avoid

• Avoid first-generation antihistamines like diphenhydramine due to lingering concerns about cleft palate association. 1, 7
• Do not use oral decongestants during the first trimester due to conflicting reports of associations with gastroschisis and small intestinal atresia. 1, 7
• Avoid levocetirizine during the first trimester due to limited safety data. 7 Despite being the active metabolite of cetirizine, it lacks the extensive pregnancy data that loratadine and cetirizine possess.
• Hydroxyzine is specifically contraindicated during early pregnancy based on animal data showing potential risks. 2, 7

Common Pitfalls to Avoid

• Do not assume all antihistamines have equivalent safety profiles—they do not. 2, 7 Loratadine and cetirizine have far more robust pregnancy data than newer agents.
• Do not unnecessarily switch medications if a patient is already doing well on loratadine before pregnancy. 2 Continuity of effective therapy is appropriate given the strong safety profile.
• Do not combine decongestants with acetaminophen or salicylates, as this may increase risk of malformations. 7

Comparative Safety

Loratadine and cetirizine are the most well-studied second-generation antihistamines in pregnancy, making them preferable to newer agents which have limited pregnancy data. 1 The main difference is that cetirizine may cause mild drowsiness in 13.7% of patients, while loratadine is generally less sedating. 2