Purpose of this research was to analyse the rare diseases drug supply paths in the Italian region of Campania (Health District 47 of the Local Medical Company Naples 1), with a particular focus on current regulations in this field, and quantify the economic incidence of such pathologies in each quarter of 2007 and 2008. Rare, or orphan, diseases are especially serious and onerous from every point of view. Patients meet significant difficulties in obtaining information and in identifying the most appropriate treatment path within the health care system. Pharmaceutical prescriptions were analysed in order to identify the number of patients for each pathology in each quarter of the years 2007 and 2008, the drugs used, the quantity of each drug, and the costs for treatments. Data show a significant increase of costs during each quarter of the year 2008, as well as from 2007 to 2008. In the absence of specific guidelines for the Campania Region, the Local Medical Company of Naples 1 has established a procedure for patients affected by rare diseases that enables them to receive at no cost products that otherwise would not be distributed for free by the health care system.