Is It Safe to Take Unisom and Vitamin B6 to Treat Morning Sickness?

A pregnant woman looking nauseous standing at the bathroom sink

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Morning sickness is something the majority of expectant parents experience at one time or another. In fact, it affects almost 75% of people who are pregnant, according to The American Academy of Family Physicians (AAFP), with about 1% experiencing the most severe form of morning sickness, hyperemesis gravidarum.

Although very few of us get the most severe cases 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 the truth is, “morning sickness” is a misnomer. It’s more like “morning, noon, and night sickness” for many of us.

Some of us find relief in the more common remedies (small, frequent meals, and plain crackers, for example). But many of us find that we need something more to get through the most intense periods of nausea and vomiting.

Taking a medication called Unisom (doxylamine) along with vitamin B6 is a remedy that many OB/GYNs have been recommending to treat morning sickness. If you are looking for a stronger treatment for morning sickness that is effective and safe, here is what you need to know about Unixom and vitamin B6.

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. Diana E. Ramos, MD, an OB/GYN and adjunct assistant clinical professor at the University of Southern California's Keck School of Medicine, explains that 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 OB/GYNs recommend you purchase 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?

ACOG verifies that taking 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,” explains ACOG.

However, you should be sure to 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.

What Form of Unisom and Vitamin B6 Should You Take?

ACOG recommends taking vitamin B6 supplements first, and adding in Unisom if that doesn’t seem to be working. Additionally, ACOG states that it is safe for pregnant people to take a prescription medication that combines both vitamin B6 and doxylamine.

As Dr. Simpson explains, this is usually a prescription medication called Diclegis. “[Prescription combination pills such as Diclgis 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 Vitamin 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.”

If you are taking a prescription like Diclegis (doxylamine and pyridoxine), 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 considered a sleep aid, which may naturally lead you to wonder if taking it will make you sleepy and if that should change how and when you take it.

In short, Unisom may make you drowsy. “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. Be sure to talk to your healthcare provider before starting any medication you have never taken.

How Long Can You Take Unisom and Vitamin B6?

You can take Unisom and B6 for as long as you need them to treat your 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 beyond this time.

How to Wean from Unisom and Vitamin 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 trying more natural 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 Modification

  • 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 protocol 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 OB/GYN or midwife about other medications or options for treating it. Whatever the case, you should always speak to your healthcare before taking any medications during pregnancy, including Unisom/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.

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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. American Family Physician. 2014;89(12):965-970.

  2. American College of Obstetricians and Gynecologists. Morning Sickness: Nausea and Vomiting of Pregnancy.

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