What antibiotics, in addition to a proton pump inhibitor (PPI), are recommended for gastritis and a clean-based 2-centimeter gastric antral ulcer with a positive biopsy for Helicobacter pylori (H. pylori) in a patient with a penicillin allergy?

From the Guidelines

For a patient with penicillin allergy who has H. pylori-positive gastritis with a clean-based 2 cm gastric antral ulcer, the recommended antibiotic regimen would be a bismuth quadruple therapy consisting of a proton pump inhibitor, bismuth subsalicylate, tetracycline, and metronidazole for 14 days, as this regimen is preferred by the Toronto Consensus and has shown superiority over clarithromycin/metronidazole triple therapy in a prospective study 1.

Key Considerations

• The patient's penicillin allergy necessitates the use of alternative antibiotics, and the bismuth quadruple therapy is a suitable option.
• The proton pump inhibitor helps reduce acid production to promote ulcer healing, while the antibiotics eradicate H. pylori infection.
• The bismuth component provides additional protection to the gastric mucosa and enhances H. pylori eradication.

Treatment Regimen

• Proton pump inhibitor (such as omeprazole 20 mg twice daily) 1
• Bismuth subsalicylate (525 mg four times daily)
• Tetracycline (500 mg four times daily)
• Metronidazole (500 mg three times daily)

Duration and Follow-up

• The treatment regimen should be administered for 14 days, as this duration has been shown to be superior to 10-day regimens 1.
• Confirmation of eradication with a urea breath test, stool antigen test, or biopsy should be performed at least 4 weeks after completing therapy and after stopping the proton pump inhibitor for at least 2 weeks.

Additional Recommendations

• The patient should avoid NSAIDs during treatment as they can impair healing and increase the risk of bleeding.
• The patient should be advised to take the proton pump inhibitor 30 minutes prior to eating or drinking on an empty stomach, without concomitant use of other anti-acids (e.g. histamine-2 receptor antagonists) 1.

From the FDA Drug Label

14.2 H. pylori Eradication in Patients with Duodenal Ulcer Disease Triple Therapy (omeprazole/clarithromycin/amoxicillin) Three U.S., randomized, double-blind clinical studies in patients with H. pylori infection and duodenal ulcer disease (n = 558) compared omeprazole plus clarithromycin plus amoxicillin with clarithromycin plus amoxicillin

For a patient with a penicillin allergy, the use of amoxicillin is contraindicated. In this case, alternative antibiotics to amoxicillin that can be used in combination with omeprazole and clarithromycin for the treatment of H. pylori infection are:

• levofloxacin
• metronidazole (not mentioned in the provided drug labels, but commonly used as an alternative)

It is essential to note that the choice of alternative antibiotic should be based on the patient's specific situation, including the severity of the penicillin allergy, the presence of other allergies or medical conditions, and the potential for drug interactions. The patient's treatment plan should be individualized and guided by a healthcare professional. 2

From the Research

Treatment Recommendations for Helicobacter pylori Infection

In a patient with a penicillin allergy and a diagnosis of gastritis along with a clean-based 2 cm gastric antral ulcer that has tested positive for Helicobacter pylori, the treatment approach must consider alternative antibiotics to penicillin due to the allergy.

Alternative Antibiotic Regimens

• The use of a proton pump inhibitor (PPI) is standard in the treatment of H. pylori infection, especially when combined with antibiotics 3, 4, 5.
• For patients allergic to penicillin, alternative antibiotics such as metronidazole, clarithromycin, or levofloxacin can be considered in combination with a PPI 4, 6.
• A quadruple therapy regimen that includes a PPI, clarithromycin, metronidazole, and an alternative to amoxicillin (due to penicillin allergy) could be effective 3.
• The choice of clarithromycin dose is important, with 500 mg twice daily being more effective than 250 mg twice daily in achieving H. pylori eradication 6.

Considerations for Treatment Duration and PPI Dosage

• The duration of treatment can vary, but 10 to 14 days of therapy is commonly recommended for optimal eradication rates 4.
• The dosage of the PPI can also impact treatment success, with high-dose PPIs potentially offering better eradication rates in certain regimens 4.

Patient-Specific Factors

• Smoking and the severity of histological gastritis can influence the success of H. pylori eradication therapy 7.
• The presence of a penicillin allergy necessitates careful selection of antibiotics to avoid cross-reactivity and ensure patient safety.