Is Bonjesta (doxylamine and pyridoxine) more effective than Unisom (doxylamine) with B6 (pyridoxine) for treating nausea and vomiting during pregnancy?

Bonjesta vs Unisom and B6 for Nausea and Vomiting in Pregnancy

Bonjesta (doxylamine-pyridoxine combination) is not significantly more effective than over-the-counter Unisom (doxylamine) with B6 (pyridoxine) for treating nausea and vomiting during pregnancy. 1

Efficacy Comparison

The combination of doxylamine and pyridoxine is recommended as first-line therapy for nausea and vomiting in pregnancy by the American Gastroenterological Association 1. However, there is no substantial evidence that the prescription medication Bonjesta provides superior clinical benefits compared to the separate over-the-counter components:

• Bonjesta is simply a delayed-release formulation containing doxylamine 10mg and pyridoxine 10mg
• The same active ingredients can be obtained by taking Unisom (doxylamine 25mg tablets, typically split) and vitamin B6 (pyridoxine) separately
• Clinical trials show modest efficacy of the combination, with improvement in nausea scores of only 0.73 points on a 13-point scale compared to placebo 2
• This improvement falls well below the clinically meaningful difference of 3 points 2

Dosing Considerations

The recommended dosing for nausea and vomiting in pregnancy:

• Pyridoxine (B6): 10-25mg every 8 hours 1
• Doxylamine: 10-20mg at bedtime or every 8 hours 1
• This can be achieved with either:
  • Bonjesta (prescription)
  • Unisom tablets (split as needed) plus separate B6 supplements

Safety Profile

Both options have similar safety profiles:

• The doxylamine-pyridoxine combination is considered safe and well-tolerated during pregnancy 1, 3
• A randomized controlled trial specifically examining maternal safety found no increased adverse events with doxylamine-pyridoxine compared to placebo 3
• Common side effects include drowsiness and fatigue 4

Cost Considerations

A significant difference between the options is cost:

• Bonjesta is a prescription medication that may be expensive, especially without insurance coverage
• Unisom and B6 supplements are available over-the-counter at a fraction of the cost

Treatment Algorithm for Nausea and Vomiting in Pregnancy

1. Start with dietary and lifestyle modifications:

   • Small, frequent, bland meals
   • High-protein, low-fat foods
   • Avoid spicy, fatty, acidic, and fried foods
   • Stay hydrated with small, frequent sips of fluid

2. First-line pharmacotherapy:

   • Begin with pyridoxine (B6) 10-25mg every 8 hours
   • If inadequate response, add doxylamine 10-20mg at bedtime or every 8 hours

3. For moderate to severe symptoms:

   • Consider ondansetron 4-8mg every 8 hours (with ECG monitoring) 1
   • Some evidence suggests ondansetron may be more effective than doxylamine-pyridoxine for reducing nausea and vomiting 5

4. For severe cases (hyperemesis gravidarum):

   • Consider hospitalization for IV fluids and medications if dehydration or >5% weight loss occurs 1

Conclusion

The evidence does not support Bonjesta offering any significant clinical advantage over the combination of over-the-counter Unisom and B6 supplements. The active ingredients are identical, and the primary difference is in formulation and cost.