H. pylori
Also called Helicobacter pylori, stomach bacteria infection.
Dr Chad OkayFounder, Suna Health3 min read. Updated .
Helicobacter pylori is a bacterium that lives in the stomach lining. In the UK prevalence is now below 15% and falling; most carriers have no symptoms. In a minority it causes gastritis, peptic ulcers, and rare cancers. Treatment is a short prescribed course of antibiotics plus a proton pump inhibitor, chosen by the prescriber following NICE guidance and local antibiotic-resistance patterns; a follow-up test confirms it has cleared.
Why it matters
H. pylori is the best-known bacterium able to thrive in stomach acid. It survives by burrowing into the stomach lining and producing urease, which neutralises acid locally. Most carriers are asymptomatic. But over decades, the immune response to H. pylori can damage the lining, producing chronic gastritis, peptic ulcers, and (rarely) gastric cancer or MALT lymphoma.
Symptoms when it does cause problems
- Burning pain in the upper abdomen, often worse on an empty stomach.
- Nausea, especially in the morning.
- Bloating and frequent burping.
- Loss of appetite and unexpected weight loss.
- Bad breath that does not respond to oral hygiene.
- Iron deficiency anaemia not explained by diet or periods.
Red flag symptoms
- Vomiting blood, or stools that look black and tarry: that is an upper GI bleed until proven otherwise. Call 999 in the UK or 911 in the US, or go straight to A&E / the emergency department. Do not drive yourself.
- Difficulty or pain on swallowing: see a doctor promptly: this needs urgent checks.
- Persistent vomiting: see a doctor promptly.
- Significant unintentional weight loss: see a doctor promptly.
- The non-emergency flags warrant urgent referral and usually endoscopy, per NICE NG12.
How it is tested
- Urea breath test (most common, non-invasive).
- Stool antigen test.
- Endoscopy with biopsy (gold standard, used when symptoms suggest ulcer or cancer).
- Stop PPI medication for at least 2 weeks before testing or you will get a false negative.
- Stop antibiotics for at least 4 weeks before testing for the same reason.
Treatment
- Eradication is a short prescribed course, usually seven days, of two antibiotics plus a proton pump inhibitor. Which antibiotics, and for how long, is the prescriber's decision, made against NICE guidance, your allergy history and local antibiotic-resistance patterns, so the exact combination varies and is not something to work out from a web page.
- Take the full course exactly as prescribed. Incomplete courses are the main driver of treatment failure and resistance.
- If the first course fails, second-line regimens exist; that conversation belongs with the prescriber.
- Confirm eradication with a follow-up test (usually a urea breath test) at least 4 weeks after finishing antibiotics and 2 weeks off any PPI, or the result can be falsely reassuring.
- Re-infection after successful eradication is rare (under 2% per year in developed countries).
Common questions
- Can I have H. pylori without symptoms?
- Yes, most carriers do. Around 50% of the global population carry H. pylori; only 10 to 20% develop symptoms over their lifetime. Routine screening of asymptomatic adults is not currently recommended.
- Is H. pylori contagious?
- Mildly. Most transmission happens in childhood within families through shared food, saliva and water. Adult-to-adult transmission is uncommon. There is no need to isolate.
- Can probiotics treat H. pylori?
- Not on their own. Saccharomyces boulardii alongside antibiotics improves eradication rates by around 10% and reduces side effects of the antibiotics; single-strain Lactobacillus has not shown a clear eradication benefit. They are an adjunct, not a replacement.
- Does H. pylori cause IBS?
- Not directly. Some people with chronic H. pylori develop IBS-like symptoms that improve with eradication. Most IBS is unrelated to H. pylori. Test only if there are upper-GI symptoms.
Sources
- NICE CG184: gastro-oesophageal reflux disease and dyspepsia in adults, investigation and management (H. pylori testing and eradication) (NICE)
- NICE QS96 statement 3: testing conditions for Helicobacter pylori (2-week PPI and 4-week antibiotic washout) (NICE)
- NICE NG12: suspected cancer recognition and referral, oesophageal and stomach cancer (NICE)
- Maastricht VI/Florence consensus report on Helicobacter pylori management, Malfertheiner et al. 2022 (Gut (PMID 35944925))
- Helicobacter Pylori (Professional reference): UK prevalence below 15% and falling; asymptomatic carriage; re-infection rate (Patient.info / EMIS)
- Gastric Cancer chapter (Helicobacter pylori, NCBI Bookshelf): IARC/WHO 1994 Group 1 carcinogen classification (NCBI Bookshelf (Yamaoka, ed.))
- Burden of gastric cancer attributable to Helicobacter pylori in 27 countries, 2022 (more than two-thirds of cases attributable) (PMC)
- Update on triple therapy for eradication of H. pylori: standard triple therapy success now 80% or less; clarithromycin resistance (Ther Adv Gastroenterol (PMC3449761))
- H. pylori recurrence after successful eradication: annual recurrence 1.45% in developed countries (World J Gastroenterol (PMC2693738))
- S. boulardii as adjuvant therapy for H. pylori eradication: 11% eradication-rate increase (RR 1.11) (Front Cell Infect Microbiol (PMC11860874))
- Halitosis and H. pylori infection: a meta-analysis (OR 4.03; eradication reduces halitosis) (Medicine (Baltimore) (PMC5265885))
- H. pylori transmission routes and recurrence: predominantly acquired in childhood within families (Gastroenterol Res Pract (PMC6502203))