What is the treatment for nausea in pregnancy?

Treatment for Nausea in Pregnancy

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

Assessment of Severity

• Nausea and vomiting affects 30-90% of pregnant women, typically beginning at 4-6 weeks, peaking at 8-12 weeks, and subsiding by week 20 1
• Severity can be quantified using the Motherisk Pregnancy-Unique Quantification of Emesis (PUQE) score:
  • Mild: score ≤6
  • Moderate: score 7-12
  • Severe: score ≥13 1
• Hyperemesis gravidarum (HG), affecting 0.3-2% of pregnant women, is characterized by intractable vomiting, dehydration, weight loss >5% of pre-pregnancy weight, and electrolyte imbalances 1

First-Line Management: Non-Pharmacological Approaches

• Diet modifications:
  • Small, frequent, bland meals 1
  • BRAT diet (bananas, rice, applesauce, toast) 1
  • High-protein, low-fat meals 1
  • Avoid spicy, fatty, acidic, and fried foods 1
• Lifestyle modifications:
  • Identify and avoid specific triggers (certain foods with strong odors or activities) 1
  • Ginger (250 mg capsule 4 times daily) 1, 2

Pharmacological Management

Mild to Moderate Symptoms

• First-line pharmacologic therapy:
  • Vitamin B6 (pyridoxine) 10-25 mg every 8 hours 1, 3
  • Doxylamine (H1-receptor antagonist) alone or in combination with pyridoxine 1, 4
  • Available in 10 mg/10 mg and 20 mg/20 mg combinations of doxylamine/pyridoxine 1
  • In France, recommended dosage for vitamin B6: 10 mg four times daily, alone or with doxylamine 4

Moderate to Severe Symptoms

• Second-line options:
  • Other H1-receptor antagonists (promethazine, dimenhydrinate) 1, 2
  • Metoclopramide 1, 2
  • Ondansetron (may be more effective than metoclopramide for nausea control) 1, 2
• For severe cases (hyperemesis gravidarum):
  • Intravenous hydration and electrolyte replacement 1
  • Intravenous glucocorticoids may be required 1, 2

Safety Considerations

• Vitamin B6 has been established as safe during pregnancy for doses up to 40-60 mg/day 4
• Higher doses of vitamin B6 (mean 132.3 mg/day) have not been associated with increased risk of major malformations 5
• Early intervention and treatment may help prevent progression to hyperemesis gravidarum 1
• Doxylamine is FDA-approved and recommended by ACOG for persistent NVP refractory to non-pharmacologic therapy 1

Special Considerations

• For women with hyperemesis gravidarum, consider:
  • Comprehensive evaluation for signs of dehydration and malnutrition 1
  • Multidisciplinary care in severe cases 1
  • Preemptive treatment with pyridoxine-doxylamine combination may reduce risk of recurrence of moderate-severe symptoms 2

Pitfalls to Avoid

• Delaying pharmacological treatment when non-pharmacological approaches fail may lead to progression to hyperemesis gravidarum 1
• Overlooking the psychological impact of severe nausea and vomiting 6
• Failing to recognize hyperemesis gravidarum as a serious condition requiring prompt medical attention 1
• Using excessive doses of vitamin B6 (>50 mg/day) without proper monitoring, although evidence suggests higher doses may be safe 5