Taking Unisom and Vitamin B6 During Pregnancy

OTC options can help relieve morning sickness and are safe to take in pregnancy

A pregnant woman looking nauseous standing at the bathroom sink

 Vesna Andjic / Getty Images

Morning sickness affects almost 75% of people who are pregnant. While home remedies and prevention strategies can be effective, sometimes they don't do enough. Many people find relief by taking Unisom and vitamin B6 for nausea and vomiting of pregnancy. Both Unisom (doxylamine) and B6 are safe throughout pregnancy, including in the first trimester.

Although very people (about 1%) get hyperemesis gravidarum, the most severe form of morning sickness, even mild or moderate morning sickness can make life downright miserable. Morning sickness can start as early as 6 weeks into pregnancy and can last up to 14 weeks, or even longer. And “morning sickness” is a misnomer. It’s more like “morning, noon, and night sickness” for many people.

If that's you, talk to a healthcare provider about trying Unisom and B6. Here's how they work to ease symptoms of nausea and vomiting of pregnancy.

How Do Unisom and Vitamin B6 Help Morning Sickness? 

The American College of Obstetricians and Gynecologists (ACOG) says that the combination of Unisom and vitamin B6 is an effective remedy for morning sickness, and can be used if recommended by your healthcare provider.

The effectiveness is in the way the ingredients work together, says Diana E. Ramos, MD, an ob/gyn and adjunct assistant clinical professor at the University of Southern California's Keck School of Medicine. Unisom is a type of antihistamine that is known to help with vomiting. B6 is a vitamin that has been shown to relieve nausea in pregnant people. Together, Unisom and B6 are known to treat cases of moderate morning sickness, after at-home remedies don’t seem to be working.

Doxylamine is often sold over-the-counter as Unisom, a sleep aid, and this medication is what most doctors recommend you use to treat morning sickness. It’s important to check the labels when you are purchasing Unisom, as doxylamine isn’t the active ingredient in all Unisom products. In some Unisom products, the active ingredient is diphenhydramine instead.

Are Unisom and Vitamin B6 Safe for Pregnant People?

Unisom and vitamin B6 are safe. “Both drugs, taken alone or together, have been found to be safe to take during pregnancy and have no harmful effects on the fetus,” says an ACOG statement.

However, speak with your healthcare provider before starting any medications, says Lynn L. Simpson, MD, an ob/gyn and the chief of the maternal-fetal medicine division at Columbia University's Irving Medical Center. Your provider can also help you figure out how to take these and what the best dosage is for you.

How to Take Unisom and Vitamin B6 

Once you and your healthcare provider have decided that Unisom and B6 are the best choices for you, you will likely have many questions about the ins and outs of taking the medication. Here is what you need to know.

Is It Safe to Combine Unisom and B6?

The ACOG recommendations suggest taking vitamin B6 supplements first, and adding in Unisom if that doesn’t seem to be working. It is also safe for pregnant people to take a prescription medication that combines both vitamin B6 and doxylamine.

This is usually a prescription medication called Diclegis (doxylamine and pyridoxine). “[Prescription combination pills such as Diclegis have been] shown to be more effective than taking Unisom and vitamin B6 separately,” says Dr. Simpson. Dr. Simpson says that for mild cases of morning sickness, taking 10 to 25 mg of vitamin B6 every 6 to 8 hours may be helpful.

How Long Do Unisom and B6 Take to Work?

Unisom is generally fast-acting, says Dr. Ramos. “In general, doxylamine works shortly after ingesting,” she says. “So, if you have nausea now, you will get relief shortly after taking it.”

If you are taking a prescription like Diclegis, relief will be slower but longer-lasting. “The prescription combination is an extended relief formulation. If you take it at night, by morning it will be taking effect,” says Dr. Ramos.

Will Taking Unisom Make You Sleepy?

Unisom is a sleep aid, so it may make you drowsy. Some providers even recommend it for occasional insomnia in pregnancy, but talk to your own doctor or midwife before taking it.

“You may want to try it at night to see how you react to the medication,” Dr. Ramos offers. At the same time, she says, all people are different and react differently to medications; this might not be an issue for you. Always talk to your healthcare provider before starting any medication you have never taken before.

How Long Can You Take Unisom and Vitamin B6?

You can take Unisom and B6 for as long as you need them to treat morning sickness, which for most people is throughout their first trimester, as morning sickness symptoms tend to decrease after that. For some people, morning sickness lasts beyond the first trimester, and you may need to continue taking Unisom and vitamin B6.

Do I Need to Wean Off of Unisom and B6?

There is no need to wean slowly from taking Unisom and vitamin B6, says Dr. Simpson. “Patients can discontinue Unisom and pyridoxine abruptly—no need to taper these medications prior to stopping them,” she says. “Usually patients can stop their medications when they have been asymptomatic for more than a week and are beyond the first trimester.”

Other Morning Sickness Remedies

Although Unisom and vitamin B6 are considered safe, most healthcare providers recommend other remedies before taking medication for morning sickness. Combining these at-home remedies with Unisom and vitamin B6 can be helpful too. Dr. Simpson’s favorite non-pharmacologic remedies for morning sickness include:

Dietary Changes

  • Eating more often
  • Eating smaller amounts
  • Eating slowly
  • Eating more bland food
  • Drinking fluids separately from solids

Avoiding Common Nausea Triggers

  • Offensive odors
  • Excessive heat
  • Humidity
  • Noise
  • Motion

A Word from Verywell

For some pregnant people, a Unisom/vitamin B6 combo isn’t enough to make morning sickness more manageable. If this is the case, you may be dealing with a more severe case of morning sickness, and you should talk to your doctor or midwife about other medications or options for treating it.

Whatever the case, always speak to your healthcare before taking any medications during pregnancy, including Unisom and vitamin B6. And never hesitate to reach out to your provider with questions or concerns along the way: That’s what they are there for.

2 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Herrell H. Nausea and vomiting of pregnancy. Am Fam Physician. 2014;89(12):965-970.

  2. American College of Obstetricians and Gynecologists. Morning sickness: Nausea and vomiting of pregnancy.

By Wendy Wisner
Wendy Wisner is a lactation consultant and writer covering maternal/child health, parenting, general health and wellness, and mental health. She has worked with breastfeeding parents for over a decade, and is a mom to two boys.