This sheet talks about using the combination of doxylamine succinate and pyridoxine hydrochloride during a pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your health care provider.

What is doxylamine succinate-pyridoxine hydrochloride?

Doxylamine succinate is an antihistamine. Antihistamines lessen the symptoms of allergic reactions and colds, and helps to treat insomnia (hard time sleeping). Pyridoxine hydrochloride is a form of vitamin B6.

The combination of 10mg of doxylamine succinate and 10mg of pyridoxine hydrochloride is a medication used to treat nausea and vomiting of pregnancy (NVP), also called “morning sickness.” For more information on NVP, please see the MotherToBaby fact sheet Nausea and Vomiting of Pregnancy (https://mothertobaby.org/fact-sheets/nausea-vomiting-pregnancy-nvp/pdf/).

In the United States, the combination of doxylamine and pyridoxine has been sold under the name Diclegis® since 2013. In Canada, it has been sold under the brand name Diclectin®.

Diclegis® and Diclectin® are delayed-release tablets available by prescription. Delayed-release means that the tablet coating prevents the ingredients from being absorbed too quickly by the body. Doxylamine succinate and/or pyridoxine hydrochloride may also be available as over-the-counter medicines (OTC).

Does taking doxylamine succinate-pyridoxine hydrochloride increase the chance for miscarriage?

Miscarriage can occur in any pregnancy. Taking doxylamine succinate-pyridoxine hydrochloride does not increase the chance for miscarriage.

Does taking doxylamine succinate-pyridoxine hydrochloride increase the chance of birth defects?

No. In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. Studies totaling hundreds of thousands of exposed pregnant women have not found that using doxylamine succinate-pyridoxine hydrochloride during pregnancy increases the chance of birth defects. The combination of doxylamine succinate and pyridoxine hydrochloride is currently recommended as a first-line treatment for NVP by the American Congress of Obstetricians and Gynecologists (ACOG) and by several medical organizations in Canada.

Could taking doxylamine succinate-pyridoxine hydrochloride cause other pregnancy complications?

No. Taking doxylamine succinate-pyridoxine hydrochloride has not been found to increase the chance of pregnancy complications.

Does taking doxylamine succinate-pyridoxine hydrochloride cause long-term problems in behavior or learning for the baby?

Studies that have followed children from ages two to seven years have not found a higher chance of behavior or learning problems in children whose mothers used doxylamine succinate – pyridoxine hydrochloride during pregnancy.

Can I breastfeed while taking doxylamine succinate-pyridoxine hydrochloride?

There are no formal studies looking at the effects of the combination of doxylamine succinate and pyridoxine hydrochloride on the breastfed infant. Antihistamines that can make mom drowsy, such as doxylamine succinate, could cause drowsiness or irritability in a breastfeeding infant. Pyridoxine hydrochloride enters the breast milk but it has not been associated with any problems in breastfeeding infants. Talk to your healthcare provider about all of your breastfeeding questions.

If a man takes doxylamine succinate-pyridoxine hydrochloride, could it affect his fertility (ability to get his partner pregnant) or increase the chance of birth defects?

There are no studies looking at possible risks to a pregnancy when the father takes doxylamine-pyridoxine. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/.

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