Zyrtec During Pregnancy & Breastfeeding

by on May 3, 2012


Pregnant women should always advise their physicians if they are taking or considering taking Zyrtec (Cetirizine). Many physicians advise against taking Zyrtec during pregnancy simply because its long-term effects on the fetus are unknown, so many pregnant women choose to seek other alternatives in order to avoid the risk.

Can Zyrtec Be Used By Pregnant Women?

Zyrtec has been assigned Pregnancy Category B by the Food and Drug Administration (FDA). This means that the drug may be taken during pregnancy only when necessary or if benefits outweigh the risks. Animal studies failed to show harm on the unborn fetus even at high dosages of this drug. However, Zyrtec has not been adequately studied on pregnant women, so the full risks remain unkown.

A study, participated by 39 pregnant women, has shown that exposure to cetirizine during the early fetal development does not affect the outcome of pregnancy. It failed to show an increase the risk of birth defects, stillbirths, spontaneous abortions, low birth weight infant, and premature births. Most of the participants used cetirizine for treatment of rhinitis and urticaria. An observational study that was conducted in England has shown the same results. Out of the 20 pregnant women who participated in the study, 4 had elective spontaneous abortion, while the rest (16 pregnant women) gave birth to normal infants.

Although these findings are reassuring, they do not rule out the possibility of risks to the infant. More well-controlled studies are required to fully understand the effects of cetirizine on pregnancy outcome and the infant.

The American College of Allergy, Asthma and Immunology (ACAAI) and the American College of Obstetricians and Gynecologists (ACOG) recommend other antihistamines that are relatively safe during pregnancy. Chlorpheniramine and tripelennamine are the recommended antihistamines for pregnant women. Second-generation antihistamines such as cetirizine (Zyrtec) and loratadine (Claritin) may be considered in patients who do not respond or who cannot tolerate the topical therapy of antihistamine. As much as possible, these drugs should be taken after the first trimester.

Can Zyrtec Be Used By Breastfeeding Women?

Animal studies show that Zyrtec passes through the breast milk. In humans, it is not clear whether this drug is passed through the breast milk. However, considering the chemical characteristics and animal studies, it is likely that the drug will pass through the human milk. Because of this, the manufacturer does not recommend use of this drug for breastfeeding women.

Small occasional doses of Zyrtec for breastfeeding women may not cause problems, but larger doses or more prolonged use can lead to possible side effects on the child and on lactation. Exposure to Zyrtec through the breast milk can cause drowsiness, irritability, colicky symptoms, and other symptoms on the breastfed child. Furthermore, very high doses of antihistamines can inhibit prolactin which is essential in the formation of breast milk.

In case use of antihistamine during breastfeeding is necessary, the British Society for Allergy and Clinical Immunology recommends the lowest effective dose. There are other similar medications that are less likely to cause side effects on the child, such as desloratadine (Clarinex), fexofenadine (Allegra), and loratadine (Claritin). Your healthcare provider may recommend these products instead of Zyrtec.

If your physician recommends using Zyrtec while breastfeeding, be sure to watch for possible changes in your child and report them to your healthcare provider.