VacA, the vacuolating cytotoxin secreted by Helicobacter pylori, is believed to be a major causative factor in the development of gastroduodenal ulcers. This toxin causes vacuolation of cultured cells and it has recently been found to form anion‐selective channels upon insertion into planar bilayers as well as in the plasmamembrane of HeLa cells. Here, we identify a series of inhibitors of VacA channels and we compare their effectiveness as channel blockers and as inhibitors of VacA‐induced vacuolation, confirming that the two phenomena are linked. This characterization opens the way to studies in other experimental systems and to the search for a specific inhibitor of VacA action.