Can Helicobacter pylori (H. pylori) treatment induce diarrhea?

H. pylori Treatment Can Cause Diarrhea

H. pylori eradication therapy commonly causes diarrhea as a side effect, with incidence rates of up to 41% during the first week of treatment. 1 This is one of the most frequent adverse events associated with the antibiotic regimens used to treat H. pylori infection.

Incidence and Mechanism of Diarrhea

• Diarrhea is one of the most common adverse effects of H. pylori eradication therapy, with studies showing it affects approximately 21-41% of patients during treatment 1, 2
• The incidence of diarrhea is highest during the first week of treatment and typically decreases over time, with rates dropping to around 9.5% by week 4 1
• Antibiotic-associated diarrhea occurs due to disruption of the normal gut microbiota by the antibiotics used in H. pylori eradication regimens 2

Standard H. pylori Treatment Regimens and Diarrhea Risk

• Standard triple therapy (PPI + clarithromycin + amoxicillin/metronidazole) is associated with significant rates of adverse events, including diarrhea 2
• Bismuth quadruple therapy and non-bismuth quadruple therapy (concomitant or sequential) are now recommended first-line treatments but can also cause diarrhea 2
• The risk of diarrhea appears to be related to the specific antibiotics used, with clarithromycin and amoxicillin combinations showing notable gastrointestinal side effects 3, 1

Evidence on Diarrhea Incidence

• A Korean study found that diarrhea was the most common adverse event during the first week of H. pylori eradication therapy, affecting 41.28% of patients 1
• Meta-analyses show that the incidence of total adverse effects in standard H. pylori therapy ranges from 24% to 36.27% in control groups not receiving probiotics 2
• Specific studies on clarithromycin-amoxicillin therapy reported mild diarrhea in approximately 7% of patients, though rates vary across different antibiotic combinations 3

Reducing Diarrhea Risk with Probiotics

• Multiple meta-analyses demonstrate that probiotic supplementation significantly reduces the risk of diarrhea during H. pylori eradication therapy 2
• The pooled odds ratio for diarrhea incidence was significantly lower in probiotic groups (OR = 0.21,95% CI: 0.06-0.74) compared to standard therapy alone 2
• A recent meta-analysis found that probiotics reduced diarrhea risk by 51% (RR = 0.49,95% CI: 0.40 to 0.61) 4
• Certain multi-strain probiotics have shown significant efficacy in preventing antibiotic-associated diarrhea during H. pylori treatment 2
• Lactobacillus-containing probiotics and Bifidobacterium longum have demonstrated particular effectiveness in reducing treatment-related side effects 2, 4

Clinical Implications and Management

• Diarrhea and other gastrointestinal adverse events can lead to poor compliance with therapy, potentially resulting in treatment failure and antibiotic resistance 5, 1
• Proactive management of potential diarrhea should be considered when initiating H. pylori eradication therapy 2, 1
• Adjunctive use of probiotics should be considered to reduce the risk of diarrhea and improve patient compliance 2, 4
• The Maastricht IV/Florence Consensus Report acknowledges that certain probiotics show promising results as adjuvant treatment in reducing side effects of H. pylori therapy 2

Important Considerations

• The severity of diarrhea is typically mild to moderate and rarely leads to treatment discontinuation 3, 1
• Diarrhea symptoms usually resolve after completion of the antibiotic course 1
• Patient factors such as alcohol consumption and coexisting medical illness were not significantly associated with diarrhea risk in some studies 1
• When selecting an H. pylori treatment regimen, clinicians should consider the potential for diarrhea and other adverse effects, especially in patients with pre-existing gastrointestinal conditions 2, 5