What can be used to manage nausea in pregnancy?

Management of Nausea and Vomiting in Pregnancy

For nausea and vomiting in pregnancy, a stepwise approach beginning with diet and lifestyle modifications, followed by vitamin B6 (pyridoxine) and doxylamine, is recommended as first-line treatment, with additional medications reserved for moderate to severe cases. 1

Assessment of Severity

Before initiating treatment, assess the severity of nausea and vomiting using the Motherisk Pregnancy-Unique Quantification of Emesis (PUQE) score:

Severity	PUQE Score
Mild	≤6
Moderate	7-12
Severe	≥13

Treatment Algorithm

Step 1: Diet and Lifestyle Modifications

• Eat small, frequent, bland meals (BRAT diet: bananas, rice, applesauce, toast)
• Focus on high-protein, low-fat meals
• Identify and avoid specific triggers (foods with strong odors, activities)
• Reduce spicy, fatty, acidic, and fried foods

Step 2: Non-Pharmacological Interventions

• Ginger 250 mg capsules four times daily 1

Step 3: First-Line Pharmacological Treatment

• Vitamin B6 (pyridoxine) 10-25 mg every 8 hours 1, 2
• If inadequate response, add doxylamine:
  • Available as combination tablets (10 mg/10 mg or 20 mg/20 mg) 1
  • For separate administration: doxylamine 10 mg up to four times daily 3

Step 4: Second-Line Pharmacological Treatment (for moderate-severe cases)

• H1-receptor antagonists: promethazine or dimenhydrinate 1
• Metoclopramide 1
• Ondansetron 1

Step 5: For Severe Cases/Hyperemesis Gravidarum

• Intravenous hydration and electrolyte replacement
• Intravenous glucocorticoids 1
• Consider hospitalization for:
  • Dehydration
  • Weight loss >5% of pre-pregnancy weight
  • Electrolyte imbalances

Safety Considerations

• The combination of doxylamine and pyridoxine has FDA Pregnancy Category A status, indicating safety during pregnancy 4
• Vitamin B6 is considered safe at doses up to 40-60 mg/day 3
• Early intervention is crucial to prevent progression to hyperemesis gravidarum 1
• For women with vomiting lasting more than 3 weeks, vitamin B1 (thiamine) replacement is necessary to prevent Wernicke's encephalopathy 2

Efficacy Evidence

• Vitamin B6 has demonstrated benefit in reducing NVP in randomized trials 2
• The combination of doxylamine and pyridoxine has shown efficacy compared to placebo, though the clinical significance of the improvement may be modest 5
• Women taking periconceptional multivitamins experience less severe NVP 2

Common Pitfalls to Avoid

1. Delaying treatment due to concerns about medication safety in pregnancy
2. Failing to recognize and treat thiamine deficiency in prolonged vomiting
3. Not escalating therapy appropriately when first-line treatments fail
4. Overlooking hyperemesis gravidarum, which requires more aggressive management
5. Not quantifying severity using a standardized tool like the PUQE score

Early and appropriate treatment of nausea and vomiting in pregnancy is essential not only for symptom relief but also to prevent progression to more severe conditions that could impact maternal and fetal outcomes.