H. pylori Eradication Regimens

Multi-drug antibiotic regimens for H. pylori

First-line in Saudi Arabia (high clarithromycin resistance): **bismuth quadruple therapy** = PPI + bismuth subsalicylate + tetracycline + metronidazole, 14 days.

Alternative first-line: **concomitant therapy** = PPI + amoxicillin + clarithromycin + metronidazole, 14 days.

Second-line: levofloxacin-based or rifabutin-based regimens.

H. pylori is genetically diverse and resistance is common. Multi-drug therapy attacks the bacterium in different ways simultaneously, reducing the chance any individual organism survives. The PPI raises stomach pH, which makes antibiotics work better. Bismuth has independent antibacterial action and protects the stomach lining.

**Bismuth quadruple therapy (14 days)**: PPI (e.g. omeprazole 20 mg) twice daily before food + bismuth subsalicylate (262 mg, 2 tabs four times daily) + tetracycline 500 mg four times daily + metronidazole 500 mg four times daily.

Take every dose. Do NOT skip. If you miss a dose, take it as soon as you remember unless it's almost time for the next dose. Avoid alcohol completely (especially with metronidazole — disulfiram-like reaction). Take antibiotics with food to reduce stomach upset.

• Severe diarrhea, especially with fever or blood — Possible C. difficile infection — see your doctor.

• Severe rash, itching, swelling — Allergic reaction — stop and seek care.

• Sun sensitivity rash with tetracycline — Avoid sun, use sunscreen.

• Severe nausea with disulfiram-like reaction (metronidazole + alcohol) — Avoid alcohol completely during and 48 hours after.

**Tetracycline**: don't take with milk, calcium, iron, antacids — separate by 2 hours. Also reduces oral contraceptive effectiveness.

**Metronidazole**: avoid alcohol (severe reaction). Increases warfarin effect.

**Clarithromycin**: many CYP3A4 interactions — review your medications.

**Bismuth**: stains nasogastric tubes; harmless dark stool.

No routine monitoring during treatment (it's only 14 days). Confirm cure with urea breath test or stool antigen 4 weeks AFTER finishing antibiotics, AND 2 weeks off PPI. Don't use blood antibody test — it stays positive even after cure.

Don't stop before 14 days unless severe side effects. Incomplete treatment causes resistance and treatment failure. If a dose is missed, just continue with the next dose — don't double up.

Tetracycline is CONTRAINDICATED in pregnancy. Treat H. pylori before pregnancy if possible. If treatment must occur during pregnancy, alternative regimens without tetracycline (e.g. amoxicillin + metronidazole + PPI) can be used after first trimester. Discuss with your doctor.

Saudi Arabia has high clarithromycin resistance (>20%), which is why bismuth quadruple is preferred first-line. Bismuth quadruple components are all available locally. MOH and most insurance plans cover the regimen.

• Why is mine 14 days instead of shorter?

• When and how should I confirm cure?

• What if my treatment fails — what's next?

• Should my family members be tested?

This guide comes from the Saudi Gastroenterology Association (SGA) patient library, prepared by the SGA Patient Education Panel. Last reviewed: 2026-04-24. It is for education and does not replace your doctor's advice.