Helicobacter pylori Infection Drug Summary

Last updated: 26 February 2025
Reviewed by

Antiulcerants

Drug Dosage Remarks
Bismuth Preparations
Bismuth subsalicylate 524 mg PO 12 hourly with 2 antibiotics and 1 PPI x 10-14 days Adverse Reactions
  • GI effects (nausea/vomiting, darkening of stool or tongue)
  • Bismuth toxicity can occur if used for long periods of time (GI disturbances, stomatitis, discoloration of mucus membranes, encephalopathy)
  • Absorption of salicylate occurs with administration of Bismuth subsalicylate
  • RBC: Headache, anemia, altered liver enzymes
Special Instructions
  • Avoid in patients with moderate-severe renal impairment
Bismuth subcitrate (Bismuth subcitrate [colloidal], Tripotassium dicitrato bismuthate)1 120 mg PO 6 hourly in combination with other drugs x 2 weeks
Histamine2-Receptor Antagonist (H2RA)
Ranitidine Duodenal ulcer associated with H pylori infection:
300 mg PO once nightly or
150 mg PO 12 hourly with Amoxicillin and Metronidazole x 14 days or
50 mg slow IV 6-8 hourly 		Adverse Reactions
  • Rare/very rare: CNS effects (dizziness, headache, reversible confusional state); Dermatologic effect (rash); Hepatobiliary effects (transient and reversible changes in LFTs, hepatitis with or without jaundice); CV effects (arrhythmias, increased BP, palpitations); Other effects (fever, bronchospasm, chest pain); Uncommon: GI effects (abdominal pain, constipation, nausea)
Special Instructions
  • Avoid with concomitant use of NSAIDs
  • Use with caution in patients with history of acute porphyria and peptic ulcer, renal and hepatic impairment, chronic lung disease, diabetes, immunocompromised, smoker
Potassium-Competitive Acid Blockers (PCABs)
Tegoprazan 50 mg PO 12 hourly x 7 days Adverse Reactions
  • GI effects (nausea, diarrhea, dyspepsia); Other effects (nasopharyngitis, viral upper respiratory tract infection[URTI]), chest discomfort)
Special Instructions
  • Avoid in patients receiving Atazanavir, Nelfinavir or Rilpivirine
  • Use with caution in patients with hepatic and renal impairment
Vonoprazan 20 mg PO 12 hourly x 7 days Adverse Reactions
  • Common: GI effects (constipation, diarrhea); Uncommon: GI effects (nausea, abdominal distension, taste disturbances, stomatitis); Hepatobiliary effects (increased aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase, abnormal liver function test); Other effect (rash)
Special Instructions
  • Avoid in patients receiving Atazanavir sulphate or Rilpivirine HCl
  • Use with caution in patients with hepatic and renal disorders
  • Increased risk for GI infection caused by C difficile and osteoporosis-related fractures of hip, wrist or spine
Proton Pump Inhibitors (PPIs)
Esomeprazole 20 mg PO 12 hourly or 40 mg PO 24 hourly Adverse Reactions
  • Generally well tolerated; most commonly reported: Headache, diarrhea, rash
  • Less common: GI effects (constipation, flatulence, abdominal pain, nausea/vomiting, dry mouth); Dermatologic effects (pruritus, urticaria); Musculoskeletal effects (arthralgia, myalgia); Hematologic effects (eosinophilia, leukopenia, thrombocytopenia); Other effects (dizziness, fatigue, insomnia, cough, URTI)
  • Hypersensitivity reaction, elevated liver enzymes, and isolated cases of photosensitivity and hepatotoxicity have been reported
Special Instructions
  • Use with caution in patients with hepatic impairment; dose adjustment recommended
  • Concomitant use with Atazanavir or Nelfinavir is not recommended (PPIs reduce exposure to these drugs)
  • Exclude possibility of gastric malignancy prior to treatment
  • Bone fracture: Several published observational studies suggest that PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist or spine; patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated
Lansoprazole 30 mg PO 12 hourly
Omeprazole2 20 mg PO 12 hourly or 40 mg PO 24 hourly or 40 mg IV bolus 24 hourly x 5 days
Pantoprazole 40 mg PO 12 hourly
Rabeprazole
(Na rabeprazole,
Sodium rabeprazole)		 10-20 mg PO 12 hourly
Combination Products
Amoxicillin/Clarithromycin/Pantoprazole Amoxicillin 1 g/Clarithromycin 500 mg/Pantoprazole 40 mg
1 tab of each drug PO 12 hourly x 1-2 weeks		 Adverse Reactions
  • GI effects (GI discomfort, stomatitis, glossitis, oral monilia, pseudomembranous colitis, hepatic dysfunction); Other effects (headache, allergic reactions)
Special Instructions
  • Avoid in patients with hypersensitivity to macrolides or penicillins, mononucleosis, lymphatic leukemia, moderate to severe hepatic or renal impairment
  • Avoid co-administration with ergot derivatives, Cisapride, Pimozide, Terfenadine or Astemizole
  • Use with caution in patients with hypersensitivity to cephalosporins or other β-lactams, hepatic or renal impairment
Clarithromycin/Metronidazole/Omeprazole Clarithromycin 250 mg/Metronidazole 400 mg/Omeprazole 20 mg
1 tab/cap of each drug PO 12 hourly x 1-2 weeks		 • See Remarks section of each individual drug component for the
   Adverse Reactions and Special Instructions
Clarithromycin/Tinidazole/Omeprazole Clarithromycin 250 mg/Tinidazole 500 mg/Omeprazole 20 mg
1 tab of each drug PO 12 hourly x 1 week
1Combination with other anti-H pylori products is available. Please see the latest MIMS for specific formulations and prescribing information.
2Combination with Sodium bicarbonate is available. Please see the latest MIMS for specific formulations and prescribing information.

Macrolide

Drug Dosage Remarks
Clarithromycin 500 mg PO 12 hourly Adverse Reactions
  • GI effects (nausea/vomiting, GI disturbances, taste disturbances, stomatitis, glossitis, tongue/tooth discoloration, loss of appetite, constipation, diarrhea, flatulence); Musculoskeletal effects (arthralgia, myalgia); CNS effects (hyperactivity, anxiety, confusion, hallucinations, headache); CV effects (palpitations, irregular heartbeat, chest pain); Renal effects (kidney inflammation, acute renal failure, interstitial nephritis); Hematologic effects (deficiencies of blood platelets, leukopenia, thrombocytopenia); Other effects (smell disturbances, hypoglycemia, hypersensitivity reactions, hearing impairment)
Special Instructions
  • May take with food to decrease gastric distress
  • Use with caution in patients with hepatic dysfunction, kidney disease, serious GI problems, heart diseases, asthma

Other Antibiotics

Drug Dosage Remarks
Nitroimidazole Derivatives
Metronidazole 400-500 mg PO 12 hourly or
500 mg IV 8 hourly x 7 days		 Adverse Reactions
  • GI effects (nausea/vomiting, metallic taste, diarrhea, constipation); CNS effects (weakness, dizziness, headache, mood changes); Renal effect (may cause darkening of urine); Other effect (candidal infection)
  • High dose or prolonged use has caused peripheral neuropathy and epileptiform seizures
Special Instructions
  • When given with alcohol, a Disulfiram-like reaction can occur
  • Use with caution in patients with severe hepatic impairment
  • If given for >10 days, recommend CBC monitoring and clinical monitoring for CNS effects
Tinidazole 500 mg PO 12 hourly Adverse Reactions
  • CNS effects (ataxia, convulsions, dizziness, headache, hyperesthesia, paresthesia, peripheral neuropathy, sensory disturbances, vertigo); GI effects (metallic taste, abdominal pain, anorexia, diarrhea, furry tongue, glossitis, nausea/vomiting, stomatitis); Other effects (dark urine, fever, tiredness, transient leukopenia, flushing)
Special Instructions
  • Use with caution in patients with current or a history of blood dyscrasias, hepatic and renal impairment

Penicillins

Drug Dosage Remarks
Amoxicillin 1,000 mg PO 12 hourly Adverse Reactions
  • Common/very common: Increased risk of infection; Uncommon: CNS effects (dizziness, headache); Other effect (dyspepsia)
  • High doses may be associated with CNS effects (encephalopathy, convulsions)
Special Instructions
  • Avoid in patients with penicillin allergy
  • Use with caution in patients with renal impairment
Amoxicillin/clavulanic acid (Co-amoxiclav,
Amoxicillin/ clavulanate) 		250-500 mg PO 8 hourly

Quinolone

Drug Dosage Remarks
Levofloxacin 500 mg PO 24 hourly Adverse Reactions
  • GI effects (abdominal discomfort, nausea/vomiting, diarrhea, increased liver enzymes); CNS effects (headache, dizziness, insomnia); Hematologic effect (changes in blood cell counts)
Special Instructions
  • Avoid in patients with epilepsy and exposure to direct sunlight
  • Use with caution in patients with renal impairment, known or suspected CNS disorder that may predispose to seizures, diabetes, heart disease, myasthenia gravis and risk of tendonitis

Supplements & Adjuvant Therapy

Drug Dosage Remarks
Fucoidan 50 mg PO 12 hourly or
100 mg PO 24 hourly		 Special Instructions
  • Avoid in patients with hypersensitivity to Fucoidan
Lactobacillus reuteri 200 mg PO 24 hourly or
900 mg PO 24 hourly or
1,400 mg PO 24 hourly		 Special Instructions
  • Should be taken with food

Tetracycline

Drug Dosage Remarks
Tetracycline 500 mg PO 6 hourly Adverse Reactions
  • GI effects (nausea/vomiting, diarrhea, antibiotic-associated diarrhea/colitis, dysphagia, esophageal ulceration when taken with an insufficient amount of liquid); Dermatologic effect (photosensitivity); Other effects (candidal infections, discoloration of teeth, interference with bone growth in young infants/pregnant women)
Special Instructions
  • Take with plenty of fluid while sitting or standing and well before retiring to bed
  • Avoid in patients with systemic lupus erythematosus (SLE)
  • Avoid long exposure to sunlight or tanning beds
  • Use with caution in patients with renal or hepatic impairment

Disclaimer

All dosage recommendations are for non-pregnant and non-breastfeeding women, and non-elderly adults with normal renal and hepatic function unless otherwise stated.  
Not all products are available or approved for above use in all countries.  
Products listed in the Drug Summary are based on indications stated in the locally approved product monographs.   
Please refer to local product monographs in Related MIMS Drugs for country-specific prescribing information.