Computer program designed by the authors and described in the article is realized as a reference system providing data on combinations of drugs used for diabetes mellitus. The system supplies information on hypoglycemic effects of representatives from each of three groups (insulins, sulfonamides, biguanides) administered both separately and in association with second drug selected by user. Interface of the system (drug menus and output windows) is friendly and demand no special training and operating skill. The program is written in C language and compiled as a single executable module for IBM-compatible personal computers.