OBJECTIVES: The aim of this study was to investigate characteristics of out-of-hours service utilization in Split owing to upper respiratory tract diseases. EXAMINEES AND METHODS: The study was conducted in the out-of-hours family medicine service „Mertojak“ in Split, during the period from January 1st to December 31st, 2012. Data were retrospectively collected from the logbook (protocol) and were processed in Microsoft Office Excel 2007. RESULTS: There were 8232 visits during 2012; there were 55% of women and 45% men. The majority of patients (82%) that visited the out-of-hours family medicine service were living in Split. The most frequent reasons for encounter were respiratory diseases (35%) and diseases of the ear (13,1%), then diseases of the skin and subcutaneous tissue (9,9%) and diseases of the musculoskeletal system and connective tissue (9%). A preponderant part of respiratory pathology was associated with upper respiratory tract, such as acute pharyngitis (33%), acute tonsillits (31%), then acute sinusitis (14%) and acute nasopharyngitis (11%). Antibiotic therapy was the most common type of prescription, and the penicillins were the most widely prescribed antibiotics. Only a small fraction of patients (1,26%) with the upper respiratory tract illness were sent to specialist consultation or to an emergency medical unit, while the bulk was sent at home treatment. The largest group of such patients were children aged 8-15 years (33%). A marked increase in visits for these ailments was observed during the winter months (71,8%). CONCLUSION: Problems related to upper respiratory tract are the most common reason for visiting the outof- hours family medicine service, and the most frequent patients were school-age children. The most prevalent diagnoses were acute tonsillitis and acute pharyngitis. A disturbingly high antibiotic prescription rate was observed for these conditions.