Researchers assess safety of bismuth compounds for treatment peptic ulcer disease

Bismuth compounds have been used for centuries in medicine.

The discovery of H. pylori in 1983 led to renewed interest in bismuth compounds, because these were found to successfully treat the infection in combination with antibiotics. However, in the 1970s bismuth salts, used at high doses for prolonged periods, were found to lead to neurotoxicity. There has been no summary of evidence for the toxicity of bismuth when used for short periods as part of H. pylori eradication therapy.

A research article to be published on December 28, 2008 in the World Journal of Gastroenterology addresses this question. The research team led by Professor Paul Moayyedi from McMaster University, Canada performed a systematic review and meta-analysis to assess the safety of bismuth compounds, when used in a 1 or 2-week course of H. pylori eradication therapy. They examined the risk of adverse events in randomized controlled trials using bismuth compounds as part of H. pylori eradication therapy compared to other regimens.

Thirty-five randomized controlled trials containing over 4500 patients were identified comparing bismuth with placebo or no treatment, or bismuth salts in combination with antibiotics as part of eradication therapy with the same dose and duration of antibiotics alone or in combination with acid suppression. There were no differences in the total number of adverse events with bismuth versus comparison regimen. Individual adverse events were also no more frequent with bismuth, with the exception of dark stools. There were no significant differences detected in the number of adverse events leading to withdrawal of therapy with bismuth versus comparison regimen.

Their results indicated that Bismuth compounds, when used as part of H. pylori eradication therapy, are safe and well-tolerated. The only adverse event occurring more frequently with bismuth compounds was dark stools, which is of little clinical significance.

These results are encouraging, because there have been recent concerns expressed that PPI-based triple therapies for H. pylori do not lead to satisfactory eradication rates, and therefore the use of bismuth containing regimens has been recommended as a potential first line therapy in the recent Maastricht guidelines. Furthermore, there are now new bismuth combinations commercially available. For these reasons it is important to be sure of the safety of bismuth compounds.