Abstract: An oral preparation for the prophylactic and/or therapeutic treatment of inflammation in the mucous membrane of mammalian gastrointestinal tract (especially the human stomach) caused by Hicobacter sp. (especially H. pylori) infection is described. The preparation comprises a prophylactically and/or therapeutically effective amount of at least one type of xanthophylles. The most preferred xanthophyll is astaxanthin which is soluble in oil, preferably naturally produced astaxanthin which is esterified with fatty acids. The oral preparation may further comprise carbohydrate structures, such as those which derive from the cell wall of the production alga Haematococcus sp. The preparation may also comprise a prophylactically and/or therapeutically effective amount of a water soluble antioxidant, such as ascorbic acid (vitamin C). The oral preparation is presented in a separate unit dose or in mixture with food.