The present invention provides a drug, a quasi drug, a food or drink product having an effect of preventing, preventing recurrence or treating digestive diseases that Helicobacter pylori participates, as well as an effect of killing Helicobacter pylori while showing little side effects and being free from any risk of the occurrence of a tolerant strain. The present invention provides a drug, a quasi drug, a food or drink product containing an effective ingredient proanthocyanidines having an effect of neutralizing (attenuating) a vacuolating toxin produced by Helicobacter pylori, particularly and preferably proanthocyanidines originated from immature apple fruit or hop bracts.