What are the recommended medications for acid reflux in pregnant women?

Acid Reflux Medications for Pregnant Women

For pregnant women with acid reflux, begin with lifestyle modifications and antacids (particularly calcium-based), then escalate to ranitidine 150 mg twice daily if symptoms persist, reserving proton pump inhibitors like lansoprazole for severe or refractory cases after the first trimester.

Treatment Algorithm

First-Line: Lifestyle Modifications

• Reduce intake of spicy, fatty, acidic, and fried foods 1
• Consume small, frequent meals rather than large portions 1
• Identify and avoid specific food triggers, particularly those with strong odors 1
• These modifications should be attempted first, as reflux affects 30-90% of pregnant women due to progesterone-induced relaxation of the lower esophageal sphincter 1, 2

Second-Line: Antacids and Sucralfate

• Calcium-containing antacids are the preferred first-line medication 3
• Magnesium-based antacids can also be used, especially in patients with preeclampsia 4
• Sucralfate 1g orally three times daily is safe and effective if antacids alone are insufficient 5, 3
• These agents have minimal systemic absorption and are considered safest during pregnancy 4

Third-Line: H2-Receptor Antagonists

• Ranitidine 150 mg twice daily is the preferred H2-blocker for persistent symptoms 2, 5, 4
• A randomized controlled trial demonstrated that ranitidine 150 mg twice daily (not once daily) reduced heartburn severity by 55.6% compared to baseline and 44.2% compared to placebo 6
• All H2-receptor antagonists can be used during pregnancy, with ranitidine having the most documented safety profile even in the first trimester 2, 5

Fourth-Line: Proton Pump Inhibitors

• Reserve PPIs for intractable symptoms or complicated reflux disease 2, 5
• Lansoprazole is the preferred PPI due to its favorable safety profile in animal studies and human case reports 2
• Available data from observational studies show no association between lansoprazole and adverse pregnancy outcomes (RR=1.04,95% CI 0.25-4.21 for major malformations) 7
• All PPIs except omeprazole are FDA category B drugs; omeprazole should be avoided 5, 4
• Consider PPIs only after the first trimester when possible, weighing benefit-harm ratio 4
• A meta-analysis of 1,530 pregnant women exposed to PPIs showed no significant increase in congenital malformations (OR=1.12,95% CI 0.86-1.45) or spontaneous abortion (OR=1.29,95% CI 0.84-1.97) 7

Important Clinical Considerations

Timing and Escalation

• Early treatment is essential to prevent progression to hyperemesis gravidarum 1
• Follow a step-up approach: only escalate therapy when the previous step fails to control symptoms 2, 5, 3
• Pharmaceutical treatments show moderate-quality evidence for complete heartburn relief (RR 1.85) compared to placebo 1

Safety During Lactation

• During breastfeeding, prefer agents with minimal systemic absorption such as sucralfate and alginic acid 4
• H2-receptor antagonists (except nizatidine) are safe during lactation 5
• For lansoprazole, the developmental benefits of breastfeeding should be weighed against potential risks, though no data exists on its presence in human milk 7

Common Pitfalls to Avoid

• Do not use sodium bicarbonate-containing antacids, as they can cause fluid retention and metabolic alkalosis 3
• Avoid metoclopramide and ondansetron before 10 weeks gestation due to potential teratogenic risks 1
• Do not prescribe omeprazole as the first-choice PPI; lansoprazole has better safety data 2, 5, 4
• Do not use once-daily ranitidine dosing; twice-daily dosing (150 mg BID) is significantly more effective 6
• Serious reflux complications during pregnancy are rare, so endoscopy and diagnostic testing are infrequently needed 2, 5