This is a 3-arm parallel group prospective randomized active-treatment clinical study. A total of 75 patients with renal calculi 10-30 mm in maximal diameter measured in abdominal CT scan will be recruited in this research protocol. Patient enrollment will be performed from patients referred to Urolithiasis Unit of the 1st Urology Department, G. Gennimatas Hospital, Aristotle University of Thessaloniki. In all potentially eligible patients full medical history, as well as demographic characteristics and drug treatment will be recorded, followed by a detailed physical examination and standard laboratory tests.