Comparison · Pregnancy Smart

Doxylamine and B6 vs. supplement alternatives

Assigned clinical reviewerMichael Yuzefovich· MD, FACOGDraft · pending clinical reviewUpdated September 18, 2026

How do the options compare?

Each option is compared on the dose that was actually studied, the size of the pregnancy dataset standing behind it, and the specific side effect it brings along.

Option	Studied pregnancy dose	Guideline support	Notes
Vitamin B6 on its own	10 to 25 mg three or four times a day	ACOG's recommended starting monotherapy, as summarized by NIH ODS	Two randomized trials found 30 to 75 mg a day significantly decreased nausea, and ODS notes this dosing can approach the 100 mg pregnancy upper limit.
Ginger, with or without B6	Studies averaged 1000 mg a day	Several studies at that average daily amount did not find an increased chance of birth defects	It can interact with medications that affect blood pressure or clotting and can lower blood sugar at high doses, so MotherToBaby says to talk with your provider before starting any supplement.
Doxylamine added to B6	Doxylamine added when B6 alone is not enough	Trials of that pairing were associated with a 70% reduction in nausea and vomiting	Studies of hundreds of thousands of women found no increased chance of birth defects. Doxylamine is an antihistamine and can make people drowsy.
The prescription delayed-release version	The same pairing in prescription form	Studies following children from ages 2 to 7 found no higher chance of behavior or learning problems	The Diclegis label recommends against use while breastfeeding, since doxylamine could cause drowsiness or irritability in a nursing infant.

Adding doxylamine to vitamin B6 is recommended when B6 alone isn't enough, which is the same combination found in Diclegis and Diclectin. 1
The doxylamine-B6 combination has been studied in hundreds of thousands of pregnancies without an identified increase in birth-defect risk. 2
The typical starting dose is two delayed-release tablets at bedtime, stepping up to four tablets a day, one in the morning, one in the afternoon, two at bedtime, if needed. 3
Ginger is a reasonable non-medication option that can be paired with vitamin B6, though there isn't much research directly comparing ginger plus B6 to doxylamine plus B6. 4
ACOG's starting dose is 10 to 25 mg of vitamin B6 three or four times a day, with doxylamine added if symptoms persist, and trials of that pairing were associated with a 70% reduction in nausea and vomiting. 5

Which option makes sense?

B6 alone is the cheapest place to start, ginger is the best-studied non-drug addition at roughly 1000 mg a day, and adding doxylamine buys the largest measured reduction at the price of drowsiness.

Disclosure: Pregnancy Smart makes supplements in this category. The comparison above is written to inform, not to steer readers toward or away from our brand.

Frequently asked questions

What's the tradeoff of doxylamine over supplement-only options?

Doxylamine typically controls nausea better, but it adds drowsiness, a plus at bedtime, sometimes a downside during the day. Supplements alone, B6, ginger, or both, skip the drowsiness but often don't control symptoms as well.

Is prescription Diclegis meaningfully different from OTC Unisom + B6?

They're the same active ingredients. Diclegis is a delayed-release formula designed to peak the next morning from a bedtime dose, while OTC Unisom SleepTabs plus B6 needs manual dose adjustment but costs a fraction as much.

Should I try ginger + B6 before adding doxylamine?

That's the standard stepped approach many providers use. When ginger plus B6 doesn't control symptoms well enough, doxylamine plus B6 is the next step. Your provider can tailor the sequence to you.

Is doxylamine + B6 safe in the first trimester?

Yes, this is the most-studied first-trimester nausea combination, with reassuring safety data across hundreds of thousands of pregnancy exposures.

References

ACOG Practice Bulletin: Nausea and Vomiting of Pregnancy
ACOG · https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2018/01/nausea-and-vomiting-of-pregnancy
Doxylamine Succinate-Pyridoxine Hydrochloride (Diclegis/Diclectin): MotherToBaby Fact Sheet
MotherToBaby · https://mothertobaby.org/fact-sheets/doxylamine-succinate-pyridoxine-hydrochloride-diclegisdiclectin-pregnancy/
Diclegis (doxylamine succinate and pyridoxine hydrochloride) Prescribing Information: FDA
FDA · https://www.accessdata.fda.gov/drugsatfda_docs/label/2013/021876s002lbl.pdf
Ginger: MotherToBaby Fact Sheet
MotherToBaby · https://mothertobaby.org/fact-sheets/ginger-pregnancy/
Vitamin B6: Health Professional Fact Sheet, NIH ODS
NIH · https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.