Comparison of Twice- and Four-times-daily Amoxicillin Administration in 2-week Tegoprazan-based H. Pylori Eradication

Gastric acid depressant play a major role in an H. pylori eradication therapy by (1) increasing the intragastric pH, which improves antibiotic stability and bioavailability; (2) increasing the intragastric pH to 6 or more, which prompts H. pylori to replicate and thus become more sensitive to antibiotics that are effective only against replicating bacteria, such as amoxicillin; (3) increasing the concentration of antibiotics in the stomach. Of antimicrobial agents against H. pylori, amoxicillin is a penicillin derivative that inhibits the synthesis of the bacterial cell wall. Therefore, amoxicillin's bactericidal effect requires the bacteria to be replicating. Amoxicillin is excreted by the kidneys, the plasma half-life is approximately 1 hour, and the bactericidal effect is time dependent. Theoretically, amoxicillin should be given 3 or 4 times daily to maximize the time above minimal inhibitory concentration (MIC) However, in most H. pylori eradication therapies, amoxicillin is given twice daily, where the estimated time above MIC attained by twice daily dosing is insufficient for amoxicillin. Because most strains of H. pylori are sensitive to amoxicillin, 3 or 4 times daily administration may be appropriate to increase the H. pylori eradication success. Nevertheless, data regarding the amoxicillin dosing interval for successful H. pylori eradication are lacking.