Bismuth salts and neurotoxicity. A randomised, single-blind and controlled study.

The aim of this work was to investigate whether the normal use of colloidal bismuth subcitrate (CBS) and bismuth subnitrate (BSN) exhibits neurotoxic side-effects. A randomised, single-blind controlled study was carried out in 66 patients with H. pylori associated gastritis. Patients were randomised to receive either amoxicillin (control group) for 4 weeks or BSN for 8 weeks or CBS for 8 weeks. Clinical and neurophysiological tests including electroneurography (ENG) and spectral electroencephalography (EEG) were performed before and after therapy. No clinically relevant changes were observed with clinical tests as well as with ENG and spectral EEG recordings within each group and between the groups. It was concluded that the normal use of CBS and BSN does not exhibit clinical neurotoxicity.