IS THERE A PLACE FOR ANTACIDS IN THE TREATMENT OF HELICOBACTER-PYLORI INFECTION

Two pilot studies were performed to determine whether aluminium-containing antacids may have a place in the treatment of Helicobacter pylori infection. The urease activity of H. pylori is cytopathic to gastric epithelium, and inhibition of this enzyme may have therapeutic potential. In the first study 24 subjects, 12 of which were infected with H. pylori, were given 1 tablet of chewable aluminium hydroxide-containing antacids 10 min before a C-14-urea breath test. Gastric urease activity was suppressed by 33.3% (p = 0.02) in the H. pylori-positive subjects (none became negative) within 40 min after administration of the tablet. Gastric H. pylori infection can be effectively eradicated by triple regimens containing bismuth salts, tetracycline, and metronidazole. Owing to adverse effects of this treatment and concern for possible neurotoxicity of bismuth, a bismuth substitute is warranted. Hence, in the second study, 20 subjects infected with H. pylori were treated with 1 antacid tablet 4 times daily between meals, plus 500 mg oxytetracycline and 200 mg metronidazole 4 times daily with meals for 2 weeks. Individual H. pylori status was assessed by the C-14-urea breath test. Four weeks after cessation of treatment, H. pylori was eradicated in 45% (9 of 20) of the subjects (95% confidence interval, 23.1-68.5%). Thirty per cent (6 of 20) observed one or more adverse effect regarded as moderate or severe, of which loose stools and headache were the most common. We conclude that the suppressive effect of antacids on gastric urease activity may be a mechanism by which aluminium-containing antacids promote peptic ulcer healing and that a low-dose regimen of antacids as a bismuth substitute in the triple treatment for H. pylori eradication is inferior to the triple treatment already established.