H. pylori Eradication Regimens
Combination of 2-3 antibiotics plus a PPI for 14 days. Take EXACTLY as directed — completion rate is critical for cure and to prevent resistance.
This article is educational and does not replace your doctor's advice. Seek urgent care for any red-flag symptoms.
Drug class
Multi-drug antibiotic regimens for H. pylori
Examples
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.
How it works
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.
What it treats
- Active H. pylori infection (positive breath test, stool antigen, or biopsy)
- Patients with peptic ulcer disease found to have H. pylori
- MALT lymphoma of the stomach (eradication often cures early disease)
- Family members of patients with gastric cancer (in some guidelines)
How to take it
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.
Common side effects
- Nausea (very common — take antibiotics with food)
- Metallic taste in the mouth (metronidazole)
- Dark or black stools (from bismuth — totally harmless)
- Black tongue (from bismuth — temporary)
- Diarrhea or stomach upset
- Headache
Serious side effects — call your doctor
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.
Interactions
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.
Monitoring
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.
When and how to stop
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.
Pregnancy & breastfeeding
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.
In the Saudi context
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.
Questions to ask your doctor
Save this list or print it before your appointment — doctors appreciate prepared patients.
- 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?
Medically reviewed by: SGA Patient Education Panel · Last reviewed 24/04/2026