Colonic diverticulosis is among the most common diseases of developed countries. Its prevalence is approximately 5 - 10% of the population by age 50, and 30, 50 and 66% of those > 50, > 70 and > 85years of age, respectively. Antibiotics have been successfully used in the treatment of uncomplicated diverticular disease; however, the use of mesalazine (alone or in combination with antibiotics) in treating uncomplicated diverticulitis has been successfully developed in recent years. Indeed, mesalazine (with or without antibiotics) showed significant superiority in improving the severity of symptoms, bowel habits, and in preventing symptomatic recurrence of diverticulitis over antibiotics alone. More-over, in light of some preliminary results, it is probable that the association of mesalazine with probiotics may in the future be the first-choice treatment for mild-to-moderate uncomplicated attacks of acute diverticulitis.