Aim. To investigate the effects of oral hypoglycemic drugs on the lithogenic properties of urine in nephrolithiasis patients with concurrent type 2 diabetes.
Materials and methods. The study comprised 376 patients with recurrent nephrolithiasis and compensated type II diabetes mellitus who attended the N.A. Lopatkin Scientific Research Institute of Urology and Interventional Radiology – branch of the NMRRC of Minzdrav of Russia and D.D. Pletnev City Clinical Hospital, Moscow Health Department in 2012–2017. Patients were divided into five groups according to the administered oral hypoglycemic agent: metformin, glibenclamide, pioglitazone, canagliflozin, vildagliptin. The control group consisted of patients receiving insulin therapy.
Results. Metformin tended to acidify urine, thus producing a negative effect on urate nephrolithiasis, which is the most prevalent form of nephrolithiasis among patients with type II diabetes. Glibenclamide, on the contrary, alkalized the urine, but urine pH did not go beyond the ranges of normal values. Pioglitazone increased urine density with a simultaneous tendency to decrease diuresis, which is bad for any form of nephrolithiasis. Empagliflozin increased diuresis due to drug-induced glucosuria and also increased renal excretion of uric acid salts. However, at normal urine pH values, the uricosuric effect of the drug did not lead to a significantly increased risk of urate stone formation. Vildagliptin did not have a significant effect on urine output, urine pH, and renal salt excretion.
Conclusion. Drug therapy for type II diabetes significantly affects the properties of urine in patients with nephrolithiasis, and it should be taken into account in the metaphylaxis of nephrolithiasis.

Keywords: metaphylaxis of nephrolithiasis, nephrolithiasis, hypoglycemic therapy, type 2 diabetes mellitus