Probiotics are beneficial bacteria that are used to redress the bacterial composition of the enteric flora which may be altered in disease. Beneficial effects of probiotics have already been described in diseases such as inflammatory bowel disease, pouchitis and non-alcoholic fatty liver disease. Probiotic bacteria have also been shown to counteract inflammatory processes by enhancing the degradation of enteral antigens, reducing the secretion of inflammatory mediators, thereby modifying in a beneficial way the balance between pro- and anti-inflammatory mediators, and stabilizing gut barrier functions. These effects may benefit PSC patients.