Rational Helicobacter pylori Therapy
There are a number of different formulations but most successful ones are based on bismuth quadruple therapy. One substitutes furazolidone (100 mg 3 times daily) for metronidazole in 14-day bismuth quadruple therapy. Another substitutes amoxicillin (1 g 3 times daily) for tetracycline. Both have proven highly effective in China and may prove especially useful in areas where furazolidone is available and tetracycline is difficult to obtain.
Furazolidone is only available in a limited number of countries but it is a highly effective antimicrobial and resistance generally is low. Furazolidone is a monoamine oxidase inhibitor and interacts with numerous other drugs and foods such that an avoidance sheet always should be provided to the patient to reduce the rate of unnecessary side effects. Where it is available it is an excellent salvage regimen but one where side effects are to be expected.
Rifabutin is used primarily as an antituberculosis drug. Resistance among H pylori is rare. The initial trials, particularly as a 7-day triple therapy, proved disappointing, but several regimens are promising and it is expected that an optimized rifabutin soon will be identified for use especially as a salvage therapy. The original successful trial (ie, 96.6%) consisted of rifabutin 150 mg daily, amoxicillin 1.5 g 3 times daily, and pantoprazole 80 mg (or an equivalent PPI) 3 times daily for 12 days. We have used this regimen with success as a salvage therapy when given for 14 days. More recent studies have tested lower doses of amoxicillin and PPI (rifabutin 150 mg once daily, amoxicillin 1 g twice daily, and esomeprazole 40 mg twice daily for 12 days) with results as low as 88.6%. Clearly, additional studies are needed to optimize the regimen in terms of dose and duration. Finally, a recent study from Western Australia evaluated the combination of a PPI, bismuth, rifabutin, and ciprofloxacin, and reported an eradication rate of 95.2% in susceptible strains. The recent increase in fluoroquinolone resistance makes it unlikely that the combination will prove useful as other than a tailored regimen, but it brings up the intriguing question regarding how much improvement, if any, would be obtained by the addition of bismuth to rifabutin triple therapy.
Salvage Therapies: After at Least 2 Treatment Failures With Different Regimens
Furazolidone Bismuth Quadruple Therapy
There are a number of different formulations but most successful ones are based on bismuth quadruple therapy. One substitutes furazolidone (100 mg 3 times daily) for metronidazole in 14-day bismuth quadruple therapy. Another substitutes amoxicillin (1 g 3 times daily) for tetracycline. Both have proven highly effective in China and may prove especially useful in areas where furazolidone is available and tetracycline is difficult to obtain.
Furazolidone is only available in a limited number of countries but it is a highly effective antimicrobial and resistance generally is low. Furazolidone is a monoamine oxidase inhibitor and interacts with numerous other drugs and foods such that an avoidance sheet always should be provided to the patient to reduce the rate of unnecessary side effects. Where it is available it is an excellent salvage regimen but one where side effects are to be expected.
Rifabutin-containing Regimens
Rifabutin is used primarily as an antituberculosis drug. Resistance among H pylori is rare. The initial trials, particularly as a 7-day triple therapy, proved disappointing, but several regimens are promising and it is expected that an optimized rifabutin soon will be identified for use especially as a salvage therapy. The original successful trial (ie, 96.6%) consisted of rifabutin 150 mg daily, amoxicillin 1.5 g 3 times daily, and pantoprazole 80 mg (or an equivalent PPI) 3 times daily for 12 days. We have used this regimen with success as a salvage therapy when given for 14 days. More recent studies have tested lower doses of amoxicillin and PPI (rifabutin 150 mg once daily, amoxicillin 1 g twice daily, and esomeprazole 40 mg twice daily for 12 days) with results as low as 88.6%. Clearly, additional studies are needed to optimize the regimen in terms of dose and duration. Finally, a recent study from Western Australia evaluated the combination of a PPI, bismuth, rifabutin, and ciprofloxacin, and reported an eradication rate of 95.2% in susceptible strains. The recent increase in fluoroquinolone resistance makes it unlikely that the combination will prove useful as other than a tailored regimen, but it brings up the intriguing question regarding how much improvement, if any, would be obtained by the addition of bismuth to rifabutin triple therapy.