THE ACTIONS OF BISMUTH IN THE TREATMENT OF HELICOBACTER-PYLORI INFECTION

Bismuth salts have been used in medicine for over three centuries, par ticularly in the treatment of dyspepsia, Commonly used agents include colloidal bismuth subcitrate (CBS), bismuth subsalicylate (BSS) and th e newer ranitidine bismuth citrate (RBC), These are safe drugs which e xert local effects on the gastroduodenal mucosa, Gastric mucosal level s of bismuth exceed the concentrations required to kill Helicobacter p ylori in vitro. The mechanisms of actions of bismuth on gastrointestin al pathogens including H. pylori are complex and include inhibition of protein and cell wall synthesis, membrane function and ATP synthesis, Adherence of H. pylori to surface epithelial cells is also impaired, Bismuth monotherapy is effective in vivo to suppress H. pylori but cur e rates are low, CBS, BSS and RBC have synergistic activity with one o r two antibiotics and are effective in eradicating H. pylori. CBS and RBC also exert other effects on the mucosa including cytoprotective an d ulcer healing properties, In addition, RBC is effective in inhibitin g gastric acid secretion.