A pharmaceutical or dietetic preparation which serves for reducing and/or blocking the adhesion of pathogenic substances and organisms to eukaryotic cells, especially mammal cells, said preparation contains at least one carbohydrate having an uronic acid unit on one of the ends thereof. 10 to 100 % of the present, terminal uronic acid units pertaining to the carbohydrates are provided with a double bond that is especially situated between the C4 and C5 atom.A pharmaceutical or dietetic preparation which serves for reducing and/or blocking the adhesion of pathogenic substances and organisms to eukaryotic cells, especially mammal cells, said preparation contains at least one carbohydrate having an uronic acid unit on one of the ends thereof. 10 to 100 % of the present, terminal uronic acid units pertaining to the carbohydrates are provided with a double bond that is especially situated between the C4 and C5 atom.
