The present study is an analysis of 177 diabetic patients treated with sulfonylurea drugs before 1961.
1) One handred and three of 177 diabetic patients had response to sulfonylurea and 33 of them continued to take the drugs over 5 years.
2) Eight of the 33 cases treated with sulfonylurea over five years had become diabetic before 39 years old.
3) Five of the 33 diabetics were treated with sulfonylurea over 9 years, and 2 of the 5 patients with tolbutamide alone.
4) The cases treated with tolbutamide alone were 18 and the patients transferred to tolbutamide from carbutamide were 5. Finally among the 33 patients, 23 patients were treated with tobutamide and 19 patients were still under the treatment of tolbutamide. In there maining 4 cases of the 23 patients, the treatment with tolbutamide was changed to the therapy with insulin or biguanide.
5) In our experience the secondary failure of sulfonylurea still occurred after the 5 years treatment with the drugs, while in long term treatment of sulfonylurea a role of therapy with tolbutamide alone seems inportant.