Helicobacter pylori and probiotics represent an evolving area of gastroenterology, with growing interest in whether beneficial bacteria can support treatment of this common stomach infection. H. pylori affects approximately 20–35% of the UK population and is the leading cause of peptic ulcers and gastritis. Whilst standard antibiotic therapy remains the cornerstone of eradication, emerging evidence suggests certain probiotic strains may enhance treatment outcomes and reduce side effects when used alongside antibiotics. This article examines the scientific evidence, clinical guidance, and practical considerations for using probiotics in H. pylori management, aligned with current NHS and NICE recommendations.

What Is Helicobacter Pylori and How Does It Affect Your Stomach?

Helicobacter pylori (H. pylori) is a spiral-shaped bacterium that colonises the stomach lining, affecting approximately 20-35% of the UK population, with rates varying by age, ethnicity and socioeconomic factors. This microorganism has evolved unique mechanisms to survive in the harsh acidic environment of the stomach, primarily through producing urease, an enzyme that neutralises gastric acid in its immediate vicinity.

The bacterium typically establishes infection during childhood and can persist for decades if left untreated. Whilst many infected individuals remain asymptomatic throughout their lives, H. pylori is the primary cause of peptic ulcer disease, responsible for approximately 90% of duodenal ulcers and 70% of gastric ulcers. The infection triggers chronic inflammation of the stomach lining (gastritis), which can progress to more serious conditions over time.

Key health implications of H. pylori infection include:

• Chronic gastritis and dyspepsia (indigestion)

• Peptic ulcer disease (gastric and duodenal ulcers)

• Increased risk of gastric adenocarcinoma (H. pylori is classified as a Group 1 carcinogen by the International Agency for Research on Cancer)

• Mucosa-associated lymphoid tissue (MALT) lymphoma

• Iron deficiency anaemia and vitamin B12 deficiency

The inflammatory response triggered by the immune system, combined with the disruption of the protective mucus layer, leads to tissue damage and potential ulceration. Symptoms may include upper abdominal pain, bloating, nausea, and in severe cases, bleeding or perforation. However, it is important to note that the majority of infected individuals never develop serious complications, and the decision to test and treat depends on individual risk factors and clinical presentation.

Can Probiotics Help Treat Helicobacter Pylori Infection?

Probiotics are live microorganisms that, when administered in adequate amounts, confer health benefits to the host. Research into their role in managing H. pylori infection has expanded considerably over the past two decades, with evidence suggesting they may serve as a useful adjunct to standard antibiotic therapy rather than a standalone treatment.

The mechanisms by which probiotics may combat H. pylori are multifaceted. Certain probiotic strains can compete with H. pylori for adhesion sites on the gastric epithelium, produce antimicrobial substances (such as organic acids and bacteriocins), and modulate the local immune response to reduce inflammation. Some strains have demonstrated the ability to inhibit urease activity, thereby reducing the bacterium's capacity to neutralise stomach acid and survive in the gastric environment.

Systematic reviews and meta-analyses indicate that specific probiotics may improve eradication rates when used alongside standard triple or quadruple therapy. Studies have shown variable improvements in eradication rates, typically ranging from 5% to 15% compared to antibiotic therapy alone, though effects are strain-specific and heterogeneous. Additionally, certain probiotics appear to reduce the frequency and severity of antibiotic-associated side effects, which is clinically relevant given that adverse effects are a major cause of treatment non-compliance.

However, it is crucial to emphasise that probiotics should not be used as monotherapy for H. pylori eradication. Current evidence does not support probiotics alone as sufficient to eliminate the infection. It should be noted that probiotics are classified as food supplements in the UK, not licensed medicines, and are not currently recommended in NICE guidance as standard care for H. pylori infection. Patients diagnosed with H. pylori infection should always receive appropriate antibiotic treatment as prescribed by their healthcare provider.

Which Probiotic Strains Are Most Effective Against H. Pylori?

Not all probiotic strains demonstrate equal efficacy against H. pylori, and the clinical benefits appear to be highly strain-specific. Research has identified several strains with potentially beneficial anti-H. pylori properties, though the quality and quantity of evidence varies between different organisms.

Lactobacillus species have been most extensively studied, with Lactobacillus reuteri, Lactobacillus acidophilus, and Lactobacillus casei showing potential benefits in clinical trials. Lactobacillus reuteri strain DSM 17938 has been studied for its ability to suppress H. pylori colonisation and reduce gastric inflammation in some trials. Some Lactobacillus strains produce antimicrobial compounds that may have activity against H. pylori.

Saccharomyces boulardii CNCM I-745, a probiotic yeast, has shown benefits in reducing antibiotic-associated diarrhoea during H. pylori treatment. Studies suggest it may help decrease gastrointestinal side effects, potentially improving treatment adherence. Its mechanism involves producing proteases that degrade bacterial toxins and modulating intestinal immune responses.

Other studied strains include:

• Bifidobacterium species – may help reduce inflammation and support eradication in some studies

• Multi-strain formulations combining several Lactobacillus and Bifidobacterium species

The dosage typically ranges from 1 billion to 10 billion colony-forming units (CFU) daily, with many clinical trials using doses at the higher end of this range. When selecting a probiotic supplement, patients should look for products that specify the exact strain designation, guarantee viable organisms until the expiry date, and ideally have supporting clinical evidence for H. pylori management. It's important to understand that no probiotic product is currently licensed in the UK specifically for H. pylori eradication.

Using Probiotics Alongside Antibiotic Treatment for H. Pylori

The standard treatment for H. pylori infection in the UK involves combination antibiotic therapy, typically comprising a proton pump inhibitor (PPI) with two or three antibiotics. NICE recommends first-line triple therapy with a PPI, amoxicillin (1g twice daily), and either clarithromycin (500mg twice daily) or metronidazole (400mg twice daily) for 7 days. For patients with penicillin allergy, a PPI plus clarithromycin plus metronidazole is recommended. When probiotics are used adjunctively, careful timing and selection are important to maximise benefits.

Optimal timing for probiotic administration remains a subject of ongoing research, but current evidence suggests starting probiotics simultaneously with antibiotic therapy and continuing for at least two to four weeks after completion. This approach helps to maintain beneficial gut flora throughout treatment and during the recovery period. Some clinicians recommend taking probiotics at a different time of day from antibiotics (e.g., antibiotics with meals, probiotics between meals) to minimise potential interference, though evidence for this practice is limited.

The primary benefits of adjunctive probiotic therapy include potential improvements in eradication rates and reduced treatment-related adverse effects. Antibiotic therapy for H. pylori commonly causes gastrointestinal disturbances including diarrhoea (occurring in 20-30% of patients), nausea, abdominal discomfort, and dysgeusia (altered taste). Probiotics may mitigate these effects by preserving intestinal microbiota diversity and function, which is disrupted by broad-spectrum antibiotics.

Patients should be advised that whilst probiotics may enhance treatment outcomes, they do not guarantee eradication. Post-treatment testing is recommended for patients with confirmed peptic ulcer disease, persistent symptoms, or MALT lymphoma, typically performed at least four weeks after completing therapy. Before testing, PPIs should be stopped for at least 2 weeks and antibiotics/bismuth for at least 4 weeks. Testing uses either a urea breath test or stool antigen test (not serology, as antibodies persist long after eradication). If initial treatment fails, second-line therapy with alternative antibiotics is required, following local antimicrobial guidance.

Potential Side Effects and Safety of Probiotics for H. Pylori

Probiotics are generally considered safe for the majority of individuals, with an excellent safety profile established through decades of use and extensive clinical research. However, as with any intervention, potential side effects and contraindications must be considered, particularly in vulnerable populations.

Common mild side effects that may occur when initiating probiotic supplementation include:

• Temporary bloating or flatulence (usually resolving within a few days)

• Mild abdominal discomfort or gurgling sensations

• Changes in bowel habit, typically increased frequency

These effects are generally transient and reflect the adjustment of the gut microbiome to the introduced organisms. Starting with a lower dose and gradually increasing can help minimise these symptoms.

Serious adverse events associated with probiotics are exceedingly rare in healthy individuals but have been reported in specific high-risk groups. Contraindications and cautions include:

• Severely immunocompromised patients (e.g., those with HIV/AIDS, undergoing chemotherapy, or taking immunosuppressive medications)

• Individuals with central venous catheters or other indwelling medical devices (particularly Saccharomyces boulardii, which carries a risk of fungaemia)

• Patients with damaged or leaky gut barriers (e.g., severe inflammatory bowel disease, short bowel syndrome)

• Critically ill patients in intensive care settings

• Those with prosthetic heart valves (theoretical risk of endocarditis)

In these populations, there have been isolated case reports of probiotic-related bacteraemia or fungaemia, though the absolute risk remains very low. Patients with these risk factors should consult their healthcare provider before commencing probiotic therapy. Pregnant or breastfeeding women should also seek clinical advice before starting supplements.

Regarding product quality, the probiotic market in the UK is not as tightly regulated as pharmaceutical medications. Patients should select products from reputable manufacturers that provide strain-specific information, guaranteed potency through expiry, and evidence of third-party testing. If any concerning symptoms develop during probiotic use—such as high fever, severe abdominal pain, or signs of systemic infection—patients should discontinue the product and seek immediate medical attention. Suspected adverse reactions can be reported via the MHRA Yellow Card Scheme.

NHS and NICE Guidance on H. Pylori Treatment Options

NICE provides comprehensive guidance on the management of H. pylori infection through its clinical guideline on dyspepsia and gastro-oesophageal reflux disease (CG184) and Clinical Knowledge Summary (CKS). The guidance emphasises an evidence-based approach to testing, treatment, and follow-up, though it does not currently include specific recommendations regarding probiotic use.

NICE recommends testing for H. pylori in patients with:

• Dyspepsia that is persistent, recurrent, or associated with alarm features

• A history of peptic ulcer disease

• Before starting or while using NSAIDs in selected patients

Testing for H. pylori in unexplained iron deficiency anaemia is supported by British Society of Gastroenterology guidance after negative endoscopy. The preferred non-invasive tests are the carbon-13 urea breath test or stool antigen test. Serology is not recommended for confirming active infection as antibodies persist after eradication. Importantly, PPIs should be discontinued for at least two weeks and antibiotics/bismuth for at least four weeks before testing to avoid false-negative results.

First-line eradication therapy recommended by NICE consists of:

• A PPI (standard dose, twice daily) plus

• Amoxicillin 1g twice daily plus

• Either clarithromycin 500mg twice daily OR metronidazole 400mg twice daily

• Duration: 7 days (though the British Society of Gastroenterology often recommends 14 days due to rising antibiotic resistance)

For patients with penicillin allergy, a PPI plus clarithromycin plus metronidazole is recommended. If first-line treatment fails, second-line therapy should use alternative antibiotics not previously used. Options include bismuth-based quadruple therapy (such as Pylera plus a PPI) or levofloxacin-based regimens, typically with specialist advice and following local antimicrobial guidance.

Whilst NICE guidance does not explicitly recommend probiotics, it does not preclude their use. Healthcare professionals may consider probiotics as an adjunct based on emerging evidence, particularly for patients at high risk of antibiotic-associated side effects. Patients should contact their GP if they experience severe side effects from treatment, if symptoms persist or worsen after completing therapy, or if alarm features develop. NICE guideline NG12 recommends urgent referral for suspected cancer with symptoms such as dysphagia (at any age), or in people aged 55 and over with weight loss and upper abdominal pain, dyspepsia or reflux. Post-eradication testing should be arranged for patients with confirmed peptic ulcer disease, persistent symptoms, or MALT lymphoma.

Frequently Asked Questions