Glucotoxicity generated by hyperglycemia creates a vicious circle worsening the imbalance of diabetes mellitus. A pump-optimized transient insulin treatment can be used to break this fate and restore some degree of insulin sensitivity in uncontrolled type 2 diabetes. The aim of this retrospective study was to evaluate type 2 diabetics with a secondary failure to a maximal oral antidiabetic therapy, treated with a transient subcutaneous insulin therapy during 3 days. The following criteria were analysed: delay before permanent insulin treatment, prognosis factors of evolution, weight evolution and glucose control in patients maintained under oral treatment. We studied 250 type 2 diabetics, and 515 insulin infusions. The average follow-up was 3.5 years. At the end of the follow-up 63 patients required insulin from the inception of the study (Group 1), 76 secondarily resumed insulin (Group 2), and 111 remained with oral treatment (Group 3). Patients in Group 1 were significantly older, with higher HbA1c and a lower body mass index (BMI). On average, the patients in Group 3 were submitted to less than 2 insulin infusions, their BMI from the beginning to the end of the follow-up remained stable, while HbA1c improved. We conclude that transient optimized insulin treatment during 3 consecutive days is effective. Thus, 45% of the initial global population remain under oral therapy after 3.5 years with a better glucose control and a stable weight.