Certain novel oral antidiabetic compositions are disclosed. These pharmaceutical compositions involve the concomitant use of two different organic chemical compounds each chosen from a separate class of known hypoglycemic agents. One class of agents involves certain known oxazolidine-2,4-dione compounds (A), while the other class is primarily concerned with a series of known hypoglycemic sulfonylureas (B). Preferred embodiments involve the use of 5-(3-thienyl)oxazolidine-2,4-dione, 5-(4-ethoxy-3...