Phenylephrine (e.g. Sudafed PE®, DayQuil®)

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 phenylephrine 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 (September 2024).

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 phenylephrine?

Phenylephrine is a decongestant. Decongestants have been used to treat nasal congestion (“stuffy nose”) caused by colds or allergies. Phenylephrine can be found in different products, including Sudafed PE®. In Canada, it may be combined with other medications in certain preparations for relieving cold or flu symptoms, such as some formulations of DayQuil ® or Tylenol Sinus ®.

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.

Some decongestants or other over-the-counter medications might have multiple active ingredients. Be sure to look at the ingredients on your medications.

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

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

It is not known if phenylephrine can make it harder to get pregnant.

Does taking phenylephrine increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. Studies have not been done to see if phenylephrine can increase the chance of miscarriage.

Does taking phenylephrine increase the chance of birth defects?

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. Studies involving more than 1,500 individuals who were pregnant and took phenylephrine in the first trimester did not show an increased chance of birth defects. In another study looking at 1,249 individuals who took phenylephrine in the first trimester, a slightly higher chance for minor differences of the eyes or ears were reported (small changes that are not birth defects). Studies on other medications that work in the same way (make blood vessels smaller) have raised questions about a small increased chance of birth defects.

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

It is not known if phenylephrine might increase the chance of 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).

Taking phenylephrine could raise your blood pressure. If you have high blood pressure, be sure to talk to your healthcare provider about medications that would be best for you.

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

Studies have not been done to see if phenylephrine can increase the chance of behavior or learning issues for the child.

3. Breastfeeding or chestfeeding while taking phenylephrine

Studies have not been done to see if phenylephrine gets into human milk. Studies in animals have shown that phenylephrine might reduce milk supply. Because there is little information about the use of oral phenylephrine while breastfeeding or chestfeeding, use of nasal sprays or other medication might be preferred. 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 phenylephrine, could it affect fertility or increase the chance of birth defects?

Studies have not been done to see if phenylephrine could affect a male’s fertility (ability to get a person 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

Phenylephrine is a decongestant used to help with stuffy nose caused by colds or allergies. It is found in products like Sudafed PE®. If you have high blood pressure, talk to your healthcare provider before taking phenylephrine.
It is not known if phenylephrine affects fertility, miscarriage risk, or pregnancy-related complications like preterm birth or low birth weight.
Studies on over 1,500 pregnant people who took phenylephrine in early pregnancy did not show a higher risk of birth defects. One study found small differences in the ears or eyes, but these are not serious birth problems.
There are no studies on whether phenylephrine passes into human milk.
There are no studies about phenylephrine and male fertility or birth defect risks, but medication taken by the father or sperm donors is not likely to increase pregnancy risks.
Always talk with your doctor, pharmacist, or nurse before starting or changing your medication during pregnancy or while breastfeeding or chestfeeding.

References

Please click here for references.

Disclaimer

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