OBJECTIVES: Sulfonylureas (SU) represent a common treatment for type 2 diabetes (T2DM), but they are associated with hypoglycemia, weight gain, and possibly cardiovascular events. The purpose of this study is to evaluate factors associated with SU discontinuation after insulin initiation. METHODS: Patients ≥21 years old with a T2DM diagnosis between 2005 and 2012 were identified using the GE electronic medical records database. Index date was defined as the first insulin prescription (Rx) between 2006 and 2011. Patients were required to be on SU at the index date. Patients were excluded if they did not have medical records available ≥12 months before and after index date, were receiving insulin in the 12 months prior to index date, or had other forms of diabetes. Treatment with other diabetes medications in addition to SU and insulin were permitted in this study. SU discontinuation occurred when the gap between the end date of current SU Rx supply and the start date of subsequent SU supply was ≥90 days apart. Multivariate logistic regression was performed to identify factors associated with SU discontinuation.  RESULTS: A total of 8,185 patients were selected, with mean age 64 years and 49% were male. 60.4% discontinued their SU Rxs within 1 year, with a median time from insulin initiation to SU discontinuation of 88 days. In the logistic regression, baseline diagnosed hypoglycemia (OR=2.29 [95% CI 1.03 - 5.10]; p=0.04) and baseline HbA1c (OR=1.04 [1.01 - 1.06]; p=0.004) were identified as factors associated with SU discontinuation. Additional factors included BMI (<25 kg/m2 vs. ≥30 kg/m2;OR=1.23 [1.03 - 1.46]; p=0.03), use of 3rd generation SU (OR=0.86 [0.78 - 0.95]; p=0.002), and chronic renal disease (OR=1.34 [1.07 - 1.67]; p=0.01).  CONCLUSIONS: In conclusion, multiple factors, including efficacy and hypoglycemia, are associated with discontinuation of SU treatment after insulin initiation.