From the Guidelines
The Society of Obstetricians and Gynaecologists of Canada (SOGC) recommends a stepwise approach to managing nausea and vomiting in pregnancy, starting with lifestyle modifications and escalating to pharmacologic interventions as needed, as supported by the most recent evidence from 2024 1.
Stepwise Approach to Management
The initial steps in managing nausea and vomiting in pregnancy include:
- Eating small, frequent meals
- Avoiding triggers
- Consuming ginger (250 mg four times daily)
- Taking vitamin B6 (pyridoxine) 10-25 mg three to four times daily If symptoms persist, adding doxylamine 10 mg with pyridoxine 10 mg (Diclectin) is recommended, starting with 2 tablets at bedtime, with additional doses in the morning and afternoon as needed, up to 4 tablets daily, as suggested by the American College of Obstetricians and Gynecologists (ACOG) and supported by recent evidence 1.
Pharmacologic Interventions
For moderate to severe symptoms, antiemetics can be added, including:
- Dimenhydrinate 50-100 mg every 4-6 hours
- Metoclopramide 5-10 mg every 8 hours
- Ondansetron 4-8 mg every 8 hours For severe, refractory cases, promethazine 12.5-25 mg every 4-6 hours or chlorpromazine 10-25 mg every 4-6 hours may be used, as recommended by recent guidelines 1.
Severe Cases
Intravenous rehydration and hospitalization should be considered for women with hyperemesis gravidarum, as early treatment of nausea and vomiting of pregnancy may reduce progression to hyperemesis gravidarum, as highlighted in the 2024 AGA clinical practice update 1.
Individualized Treatment
Treatment should be individualized based on symptom severity, patient preference, and response to therapy, with the goal of minimizing morbidity, mortality, and improving quality of life for pregnant women experiencing nausea and vomiting, as emphasized by the SOGC guidelines and supported by recent evidence 1.
From the Research
SOGC Guidelines for Nausea and Vomiting in Pregnancy
- The Society of Obstetricians and Gynaecologists of Canada (SOGC) guidelines for nausea and vomiting in pregnancy recommend doxylamine-pyridoxine as a first-line treatment 2.
- A study published in the Journal of Clinical Pharmacology found that doxylamine succinate-pyridoxine HCl was more effective than pyridoxine alone in reducing nausea and vomiting symptoms in pregnant women 3.
- Another study published in PLoS ONE found that doxylamine-pyridoxine was associated with improved symptoms of nausea and vomiting in pregnancy compared to placebo, although the difference was not statistically significant using all approaches to handling missing data 2.
- A systematic review published in JAMA found that ginger, vitamin B6, antihistamines, metoclopramide, pyridoxine-doxylamine, and ondansetron were associated with improved symptoms of nausea and vomiting in pregnancy compared to placebo 4.
Treatment Options
- Doxylamine-pyridoxine is a commonly prescribed medication for nausea and vomiting in pregnancy 2, 3.
- Pyridoxine (vitamin B6) is also used to treat nausea and vomiting in pregnancy, although it may not be as effective as doxylamine-pyridoxine 3.
- Other treatment options include ginger, antihistamines, metoclopramide, and ondansetron 4.
- Corticosteroids may be associated with benefit in severe cases of nausea and vomiting in pregnancy 4.
Safety and Efficacy
- Doxylamine-pyridoxine has been shown to be safe and effective in reducing nausea and vomiting symptoms in pregnant women 2, 3.
- A study published in the Israel Medical Association Journal found that bi-daily combination therapy with pyridoxine and doxylamine was safe and had comparable efficacy to metoclopramide in treating nausea and vomiting in pregnancy 5.
- The American College of Obstetricians and Gynecologists (ACOG) recommends that treatment for nausea and vomiting in pregnancy be individualized and based on the severity of symptoms 6.