OBJECTIVES: Diabetes mellitus (DM) is the second most expensive chronic disease in Italy after cancer with total direct costs over €9 billion (2012), 70% of which attributable to hospitalizations and 30% to drug treatments. The objectives of the present study were to assess the trend in pharmaceutical and hospital expenditure of diabetes in Italy during 2013-2015. METHODS: Antidiabetic drugs consumption and expenditure indicators in the last available three years (2013-2015) were analyzed from the Observatory on the Use of Medicines (OSMED) published reports, to determine trends in consumption and expenditures. Data before 2013 were inconsistent and therefore excluded from the analysis. Consumption was determined according to defined daily dose (DDD)/1,000 inhabitants. Expenditure was referred to per-capita spending on territorial drugs. Data on hospital discharge for diabetes (main cause, i.e. DRGs 294-295) from the Health Ministry were matched with last published DRGs Tariffs to estimate the hospitalizations costs. RESULTS: In Italy, consumption of antidiabetic drugs per DDD/1,000 inhabitants was respectively, 62.8 in 2013 and 62.6 in 2015 while per-capita expenditures were €13.63 in 2013 and €14.26 in 2015. Surprisingly a slight decrease in the off-patent antidiabetic drugs consumption was observed in the period 2013 to 2015 for Italy, representing 59.5% of DDD and 20.1% of total drug expenditure in 2013 vs 59.4% DDD and 19.6% of total drug expenditure in 2015. Hospitalizations and related costs for diabetes showed a reduction in the analyzed period with 19,199 admissions (Day-hospitals 6.2%) for a cost of €27,029,044 in 2013 vs. 16,762 admissions (Day-hospitals 5.6%) equal to €23,497,024 in 2015. CONCLUSIONS:  Despite the limitations, the data show a stable trend in diabetes expenditure with a slight increment in per-capita expenditures, probably due to introduction of new expensive drugs, and a reduction in hospital admissions leading to a decrease in hospitalization costs.