The present invention provides a pharmaceutical composition comprising a probiotic and a prebiotic for preventing acquisition of and/or alleviating symptoms associated with an infection caused by an Extended-spectrum beta-lactamases (ESBL) producing organism and other drug resistant pathogens. More particularly, the pharmaceutical composition comprises at least one Lactillobacillus specie(s) as a probiotic and at least one oligosaccharide as a prebiotic. The present invention further provides a method of preventing acquisition of and/or treating an infection caused by Extended-spectrum beta-lactamases (ESBL) producing bacteria and other drug resistant pathogens, comprising administering an effective amount of a pharmaceutical composition comprising a probiotic and a prebiotic to a subject in need thereof.