OBJECTIVES: To develop a Budget Impact Model (BIM) to estimate the financial consequences of the use of levofloxacin for the treatment of community-acquired pneumonia (CAP) in Italian Hospitals to support health decision makers. METHODS: We developed a BIM for levofloxacin that compares current treatments for CAP, their efficacy and safety and the resource use and costs as apply to the population of interest. Several dimensions were considered: drug consumption, frequency and days of treatment, health care professional costs, disposable (material), hospitalization costs and need of a second line treatment. Different scenarios in antibiotic treatment of CAP were included for comparison,  such as i.v. therapy or switch therapy and  levoxacin is compared to current alternative in monotherapy and in combination therapy. RESULTS: CAP is an infection still associated to considerable rates of morbidity and mortality and with important consequences from the social and economic perpspective. In Italy the annual incidence of hospitalization due to CAP is about 3 cases every 1000 habitants, with rather high mortality rates: from 15/100.000 cases of the national mean to 70/100.000 cases for subjects older than 65 years. More than 90% of CAP costs are associated to hospitalizations (500 million euro. The model we developed  results in an interactive tool that allows users (payers) to understand the relation between the characteristics of their scenario and the possible budget consequences of the different treatment choices and informs them about the most affordable option among current treatments for CAP (including levofloxacin) according to the features of their own scenario CONCLUSIONS:  BIMs are primarily intended to inform health care decision makers, especially those who are responsible for national, regional, or local health care budgets. For this reason methodology and results were  reviewed in an external engagement with payers to validate the model in a real scenario.