Loratadine
MedicationClaritin, Alavert
Second-generation antihistamine
Research strength: 3 / 5
MotherToBaby says loratadine is not expected to raise the overall chance of birth defects, but this omits signals in two US birth-defect studies. In 2009, researchers reported an association with transverse limb deficiency, a rare defect involving a missing part of an arm or leg (OR 2.04, 95% posterior interval 1.04-4.03). An expanded 2020 study used overlapping data, grouped loratadine with desloratadine, and reported signals for a rare heart defect, kidney development defects, and duodenal atresia or stenosis, based on 8, 10, and 12 exposed cases. The 2020 study tested 340 medicine-defect comparisons and its authors said the findings were not strong evidence of a link; it found no significant hypospadias association, although the estimate was borderline (aOR 1.32, 95% CI 1.00-1.73). The 2003 EMA committee recommended a precautionary label statement that loratadine use in pregnancy was not recommended while causality remained uncertain, whereas current NHS SPS lists loratadine as preferred; the Claritin label asks pregnant users to consult a health professional. Ask your provider about your situation.
Last reviewed: 2026-10-16
Sources
- MotherToBaby: Loratadine (Claritin) fact sheetUS government
- Gilboa et al., 2009: NBDPS antihistamine studyUS government
- Hansen et al., 2020: NBDPS antihistamine studyUS government
- EMA CPMP Article 31 opinion on loratadineEU agencyEuropean guidance
- NHS Specialist Pharmacy Service: Hay fever treatment during pregnancyUK government
- DailyMed: Claritin 10 mg loratadine tablet labelDrug company label
Research strength: 3 / 5
MotherToBaby reports that pregnancy studies have not found an increased chance of birth defects, preterm delivery, or low birth weight, but its fact sheet does not separate these outcomes by trimester. The expanded 2020 US study reported 10 positive findings in its second-trimester-only sensitivity analysis, all involving other antihistamines; loratadine was not listed in the supplement table. Its authors cautioned that many results across hundreds of comparisons could be due to chance or other factors. NHS SPS lists loratadine as preferred during pregnancy, while the EMA's 2003 committee recommended a precautionary label statement; the Claritin label asks pregnant users to consult a health professional. Ask your provider about your situation.
Last reviewed: 2026-10-16
Sources
- MotherToBaby: Loratadine (Claritin) fact sheetUS government
- Hansen et al., 2020: NBDPS antihistamine studyUS government
- EMA CPMP Article 31 opinion on loratadineEU agencyEuropean guidance
- NHS Specialist Pharmacy Service: Hay fever treatment during pregnancyUK government
- DailyMed: Claritin 10 mg loratadine tablet labelDrug company label
- Hansen et al., 2020: Supplemental Tables S1-S7US government
Research strength: 3 / 5
MotherToBaby reports that pregnancy studies have not found an increased chance of preterm delivery or low birth weight, but its fact sheet gives no third-trimester-only results. The pregnancy cohorts and NBDPS analyses reviewed here report early-pregnancy outcomes, and the NBDPS second-trimester sensitivity analysis does not provide third-trimester data. The NBDPS authors reported specific rare-defect signals in early pregnancy but cautioned that hundreds of comparisons could produce chance findings. The EMA's 2003 committee recommended a precautionary label statement while causality remained uncertain, whereas current NHS SPS lists loratadine as preferred; the Claritin label asks pregnant users to consult a health professional. Ask your provider about your situation.
Last reviewed: 2026-10-16
Sources
- MotherToBaby: Loratadine (Claritin) fact sheetUS government
- Hansen et al., 2020: NBDPS antihistamine studyUS government
- EMA CPMP Article 31 opinion on loratadineEU agencyEuropean guidance
- NHS Specialist Pharmacy Service: Hay fever treatment during pregnancyUK government
- DailyMed: Claritin 10 mg loratadine tablet labelDrug company label
Loratadine — Breastfeeding
Research strength: 4 / 5
LactMed reports that after one 40 mg dose in six women, the estimated infant dose through milk averaged 0.46% of the mother's weight-adjusted dose; 40 mg is four times the usual 10 mg dose. Two of 51 surveyed mothers reported minor infant sedation, and one reported reduced milk supply; NHS SPS reports the same survey and lists loratadine as preferred for breastfeeding full-term, healthy infants. NHS SPS recommends monitoring for infant drowsiness, irritability, poor feeding, or inadequate weight gain. On milk supply, NHS SPS says usual doses are unlikely to affect established lactation but acknowledges occasional reports, while LactMed and MotherToBaby note a possible decrease, especially with pseudoephedrine or other medicines. Ask your provider about your situation.
Last reviewed: 2026-10-16
Sources
- LactMed: LoratadineUS government
- Hilbert et al., 1988: Loratadine excretion in human breast milkUS government
- NHS Specialist Pharmacy Service: Antihistamines during breastfeedingUK government
- MotherToBaby: Loratadine (Claritin) fact sheetUS government
Pregnancy
Moretti et al. (2003) prospectively followed 161 first-trimester loratadine exposures; five malformations were observed compared with six among unexposed controls, with no significant difference. The same study reported similar live-birth rates, gestational age, and birth weight, but its abstract does not give miscarriage results. Diav-Citrin et al. (2003) followed 210 loratadine-exposed pregnancies, 77.9% in the first trimester; overall congenital anomaly rates were 4/175 (2.3%) among loratadine exposures and 25/844 (3.0%) among controls, with no significant difference. The 2009 National Birth Defects Prevention Study (NBDPS) reported one positive loratadine finding among 364 tested medicine-defect pairs: transverse limb deficiency (posterior OR 2.04; 95% posterior interval 1.04-4.03). An expanded NBDPS analysis used overlapping data from 1997-2011 and grouped loratadine with desloratadine. It reported main-analysis signals for truncus arteriosus (8 exposed cases; adjusted OR 2.66), bilateral renal agenesis or hypoplasia (10 exposed cases; adjusted OR 2.56), and duodenal atresia or stenosis (12 exposed cases; adjusted OR 2.08). The 2020 study ran 340 main analyses, and its authors said few results were consistent with previous findings and that there was not strong evidence linking antihistamines to birth defects. It found no significant loratadine-hypospadias association but reported a borderline estimate (adjusted OR 1.32, 95% CI 1.00-1.73). Kallen and Olausson's 2006 follow-up and a 2008 meta-analysis of 453,053 male births did not confirm an increased hypospadias association (adjusted OR 1.28, 95% CI 0.69-2.39). A 2026 review of 45 sources reports no significant associations between second-generation antihistamines and major pregnancy outcomes in large cohort studies, but the abstract is class-level and does not give loratadine-specific estimates.
Breastfeeding
Hilbert et al. (1988) gave a single 40 mg dose to six lactating, nonpregnant volunteers. Over 48 hours, 11.7 micrograms of loratadine equivalents were excreted in milk, equal to 0.029% of the administered dose; the estimated infant dose was 0.46% of the maternal dose by weight. LactMed estimates that the total milk dose after 10 mg would be about 3 micrograms, and the maximum calculated weight-adjusted relative dose after 40 mg was 1.1%. LactMed and NHS SPS report a survey of 51 mothers: two reported minor infant sedation and one reported decreased milk production. NHS SPS lists loratadine as preferred during breastfeeding for full-term, healthy infants but recommends monitoring for drowsiness, irritability, poor feeding, and inadequate weight gain. NHS SPS says usual doses are unlikely to affect established lactation, while acknowledging occasional reports; LactMed and MotherToBaby note possible reduced supply, especially with pseudoephedrine or other medicines.
The matched Claritin OTC label identifies loratadine 10 mg as the active ingredient in each tablet and lists corn starch, lactose monohydrate, and magnesium stearate as inactive ingredients. The label says pregnant or breastfeeding users should ask a health professional before use. This entry covers loratadine alone, not combination loratadine-pseudoephedrine products.
What was tested
Human pregnancy evidence includes prospective cohorts, registry analyses, and case-control studies. The NBDPS studies relied on retrospective maternal reports of medication use; the 2009 analysis tested 364 medicine-defect pairs, while the 2020 expansion used an overlapping cohort and 340 main analyses, grouping loratadine with desloratadine. The expanded study also ran a second-trimester-only sensitivity analysis, but its supplement listed no loratadine-associated finding in that trimester. The 2020 study did not report third-trimester-only results. Breastfeeding evidence includes one six-volunteer milk-level study after a single 40 mg dose and small survey reports from 51 mothers.
How to describe birth-defect evidence in early pregnancy
- Source A says
- MotherToBaby says loratadine is not expected to raise birth-defect chances and that other studies have not found an increased chance of any type of birth defect. Earlier cohorts and a meta-analysis did not find an overall increase or confirm a hypospadias association. (MotherToBaby: Loratadine (Claritin) fact sheet, Moretti et al., 2003: First-trimester loratadine cohort, Diav-Citrin et al., 2003: Prospective controlled cohort, Kallen and Olausson, 2006: Swedish registry follow-up on hypospadias, Schwarz et al., 2008: Hypospadias systematic review and meta-analysis)
- Source B says
- Two US NBDPS case-control analyses reported isolated associations between early-pregnancy antihistamine exposure grouped as loratadine and specific defects. The 2009 study reported transverse limb deficiency; the expanded 2020 study reported signals for truncus arteriosus, kidney development defects, and duodenal atresia or stenosis. (Gilboa et al., 2009: NBDPS antihistamine case-control study, Hansen et al., 2020: NBDPS antihistamine case-control study)
- Why they differ
- MotherToBaby summarizes broader results and the hypospadias follow-up, while the NBDPS studies screened hundreds of specific medicine-defect pairs and detected rare outcome signals. The 2020 analysis overlapped the 2009 cohort, grouped loratadine with desloratadine, and reported small exposed-case counts. The NBDPS authors warned that many positive findings could be chance or reflect other factors, but these results do not support a categorical statement that no type of defect association has been reported.
- Other sources
- A 2026 review reports no statistically significant association between second-generation antihistamines and major congenital malformations in large cohort studies, but its abstract gives class-level results rather than loratadine-specific estimates. (Lisiecka and Luczak, 2026: Systematic review of antihistamines in pregnancy)
- What the evidence shows overall
- The available evidence does not establish that loratadine caused the rare defects reported in the NBDPS analyses. Public wording should describe those signals and their study limitations rather than say that no birth-defect association has been reported.
Pregnancy recommendation from EMA and current NHS SPS guidance
- Source A says
- The EMA's 2003 CPMP opinion recommended a precautionary label statement that loratadine use during pregnancy was not recommended because a causal relationship could neither be confirmed nor excluded. (EMA CPMP Article 31 opinion on loratadine, English Annex)
- Source B says
- NHS SPS currently lists loratadine and cetirizine as the preferred antihistamines for pregnant women. (NHS Specialist Pharmacy Service: Hay fever or allergic rhinitis treatment during pregnancy)
- Why they differ
- The EMA opinion followed the Swedish registry hypospadias signal and explicitly described its warning as precautionary. The NHS SPS page was updated in 2025 and reflects later evidence and current professional guidance. The EMA decision is historical, not a new safety action.
- What the evidence shows overall
- These sources disagree in emphasis. The precaution is reported with its date and uncertainty, while current NHS SPS guidance and later studies are also described.
Possible effect on milk supply during breastfeeding
- Source A says
- LactMed and MotherToBaby note that loratadine may reduce milk supply, particularly with pseudoephedrine or other medicines. (LactMed: Loratadine, MotherToBaby: Loratadine (Claritin) fact sheet)
- Source B says
- NHS SPS says usual therapeutic doses are unlikely to affect established lactation, while acknowledging occasional reports of reduced supply with loratadine. (NHS Specialist Pharmacy Service: Using antihistamines during breastfeeding)
- Why they differ
- Evidence is limited and reports are uncommon. Guidance weighs the single reported supply decrease and possible effect of combination medicines against the lack of evidence that usual doses commonly affect established milk production.
- What the evidence shows overall
- The evidence supports mentioning a possible effect without implying that reduced milk supply is expected. NHS SPS also recommends monitoring the infant and notes that occasional reports exist.
Infant monitoring during breastfeeding
- Source A says
- LactMed says low milk levels mean adverse effects would not be expected in most breastfed infants; MotherToBaby describes loratadine as a preferred antihistamine because it is less likely to cause drowsiness than some alternatives. (LactMed: Loratadine, MotherToBaby: Loratadine (Claritin) fact sheet)
- Source B says
- NHS SPS lists loratadine as preferred but recommends monitoring for infant drowsiness, irritability, poor feeding, and inadequate weight gain. (NHS Specialist Pharmacy Service: Using antihistamines during breastfeeding)
- Why they differ
- LactMed and MotherToBaby describe expected effects based on low exposure and limited reports. NHS SPS adds precautionary monitoring because the evidence is limited and includes occasional reports of infant sedation.
- What the evidence shows overall
- The sources agree that loratadine is a preferred non-sedating antihistamine during breastfeeding, but differ in how strongly they state monitoring. The summary attributes NHS SPS's monitoring advice and reports the small survey results.
- NHS SPS recommends non-drug measures first, then topical treatment or an oral antihistamine if needed; it lists loratadine and cetirizine as preferred antihistamines for pregnant women. (NHS Specialist Pharmacy Service)
- The Claritin label states: If pregnant or breast-feeding, ask a health professional before use. (DailyMed: Claritin label)
- NHS SPS lists loratadine as preferred during breastfeeding for full-term, healthy infants and recommends monitoring for drowsiness, irritability, poor feeding, and inadequate weight gain. (NHS Specialist Pharmacy Service)
General research, not specific to pregnancy.
The Claritin label identifies loratadine 10 mg as an over-the-counter antihistamine for allergy symptoms.
- MotherToBaby lists sneezing, runny nose, watery eyes, itchy throat, and hives among symptoms treated with loratadine. (MotherToBaby: Loratadine (Claritin) fact sheet)
- The Claritin tablet label identifies loratadine 10 mg as its active ingredient. (DailyMed: Claritin 10 mg loratadine tablet label (Bayer HealthCare LLC))
- MotherToBaby: Loratadine (Claritin) fact sheetUS governmentSecondaryPage dated 2026-02-01
- LactMed: LoratadineUS governmentSecondaryPage dated 2026-02-15Independent check
- NHS Specialist Pharmacy Service: Hay fever or allergic rhinitis treatment during pregnancyUK governmentSecondaryPage dated 2025-01-31Independent check
- NHS Specialist Pharmacy Service: Using antihistamines during breastfeedingUK governmentSecondaryPage dated 2026-02-05Independent check
- DailyMed: Claritin 10 mg loratadine tablet label (Bayer HealthCare LLC)Drug company labelTertiaryPage dated 2025-12-05
- EMA CPMP Article 31 opinion on loratadine, English AnnexEU agencySecondaryPage dated 2004-04-28Independent checkEuropean guidance
- Moretti et al., 2003: First-trimester loratadine cohortUS governmentPrimaryIndependent check
- Diav-Citrin et al., 2003: Prospective controlled cohortUS governmentPrimaryIndependent check
- Kallen and Olausson, 2006: Swedish registry follow-up on hypospadiasUS governmentPrimaryIndependent check
- Schwarz et al., 2008: Hypospadias systematic review and meta-analysisUS governmentPrimaryIndependent check
- Gilboa et al., 2009: NBDPS antihistamine case-control studyUS governmentPrimaryIndependent check
- Hansen et al., 2020: NBDPS antihistamine case-control studyUS governmentPrimaryIndependent check
- Hansen et al., 2020: NBDPS supplemental Tables S1-S7US governmentPrimary
- Hilbert et al., 1988: Loratadine excretion in human breast milkUS governmentPrimaryIndependent check
- Lisiecka and Luczak, 2026: Systematic review of antihistamines in pregnancyUS governmentPrimaryIndependent check
Last reviewed 2026-10-16
Independent check 2026-10-16
Not yet clinician-reviewed
Ask your provider about your situation.