Fexofenadine (Allegra®)

Last Update: 20 Jun 2025

Medication

Table of content

1. What is it? 2. What are the risks according to research? 3. Breastfeeding/ chestfeeding 4. What about fathers and sperm donors? 5. Key points

Welcome to our fact sheet on fexofenadine during pregnancy and breastfeeding or chestfeeding. This information is based on available published literature. It should not take the place of medical care and advice from your healthcare provider.

The HEALTHY PREGNANCY HUB team is collaborating with MotherToBaby to share information on this topic. The original version is available here (August 2023).

Serene, our chatbot, can also answer your questions about medications during pregnancy.

Please note that this fact sheet is based on United States information and has been adapted for Canada, with a review by our Canadian experts. Minor differences may exist between the two countries. Always consult your healthcare professional for information tailored to your situation.

1. What is fexofenadine?

Fexofenadine is an over-the-counter antihistamine that has been used to treat and prevent allergy symptoms such as sneezing, runny nose, watery eyes, itching, and hives. Some brand names are Allegra® and Aller-Ease®.

Sometimes when people find out they are pregnant, they think about changing how they take their medication, or stopping their medication altogether. However, it is important to talk with your healthcare providers before making any changes to how you take your medication. Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy.

2. What does research say about the risks during pregnancy?

I take fexofenadine. Can it make it harder for me to get pregnant?

Studies have not been done in humans to see if taking fexofenadine could make it harder to get pregnant. Animal studies have not shown that taking fexofenadine would affect fertility (ability to get pregnant).

Does taking fexofenadine increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. One study that compared the use of fexofenadine to other common allergy medications during pregnancy found no difference in the chance of miscarriage in those who took fexofenadine.

Does taking fexofenadine increase the chance of birth defects?

Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. Studies on fexofenadine have not found an increased chance of birth defects.

Does taking fexofenadine in pregnancy increase the chance of other pregnancy-related problems?

A study that compared the use of fexofenadine to other similar antihistamines did not find an increased chance for other pregnancy-related problems, such as preterm delivery (birth before week 37) or low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth).

Does taking fexofenadine in pregnancy affect future behavior or learning for the child?

Studies have not been done to see if fexofenadine can cause behavior or learning issues for the child.

3. Breastfeeding or chestfeeding while taking fexofenadine

Fexofenadine gets into human milk in small amounts. This amount is likely too low to cause problems for the baby. Be sure to talk to your healthcare provider about all your breastfeeding or chestfeeding questions. Be sure to talk to your healthcare provider about all your breastfeeding or chestfeeding questions.

4. What about fathers and sperm donors?

If a male takes fexofenadine, could it affect fertility or increase the chance of birth defects?

Studies have not been done to see if fexofenadine could affect a male’s fertility (ability to get partner pregnant) or increase the chance of birth defects. In general, exposures that fathers or sperm donors have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures here.

Key points

Fexofenadine (Allegra®) is a medication from the antihistamine group that you can buy without a prescription. Antihistamines are used to help with allergy symptoms like sneezing, runny nose, or itchy eyes.
There are not enough studies to know if fexofenadine can make it harder to get pregnant or affect a child’s behavior or learning in the future.
So far, studies have not found a higher chance of birth defects, miscarriage, preterm birth or low birth weight, based on comparisons with other allergy medications.
There are no studies on whether fexofenadine affects a child’s
Fexofenadine can pass into breast milk in small amounts, but this is likely too little to cause problems for most babies.
There are no studies on how fexofenadine affects male fertility or birth defect risks, but medicine taken by the father or sperm donor is unlikely to affect the baby.
Always talk with your healthcare professionals before starting or changing your medication during pregnancy or while breastfeeding or chestfeeding.

References

Please click here for references.

Disclaimer

HEALTHY PREGNANCY HUB provides a source of information validated by health professionals; however, this information is provided for informational purposes only and should not replace professional advice. Medical standards and practices evolve as new data becomes available, so it is imperative to consult your doctor or a qualified health professional for any questions or concerns regarding your health without delay or omission. It is the responsibility of your treating physician or any other health professional, based on their independent experience and knowledge of the patient, to determine the best way to evaluate and treat you.

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While consulting symptoms or other medical information on our platform may guide your discussions with your healthcare professional, this information should not be used to make a medical diagnosis or determine treatment. Before making changes to your supplement or medication regimen, please discuss with your medical team or contact 811 (Canada) to ensure the relevance of these changes to your individual situation.

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