OBJECTIVE: Hyperglycemic crisis encompasses a group of diabetes emergencies characterized by insulin deficiency with high morbidity and mortality. Cocaine use is increasingly prevalent in the United States and may be associated with increased risk of diabetic ketoacidosis. The objective was to determine if active cocaine use at hospital admission could be considered a risk factor for development of hyperglycemic crisis. METHODS: A retrospective case-control analysis was performed on 950 inpatients with hyperglycemia at an urban academic hospital. Patients admitted with non-emergent hyperglycemia were compared to patients who met criteria for diabetic ketoacidosis (DKA), hyperosmolar hyperglycemic state (HHS), and hyperosmolar ketoacidosis (HK), based on the absence or presence of cocaine metabolites on urine toxicology screen. Outcomes included frequency of cocaine use in patients with DKA, HHS, HK, and non-emergent hyperglycemia; phenotypic characteristics of cocaine users vs. non-users with hyperglycemia; phenotypic characteristics of patients with hyperglycemic crisis vs. non-emergent hyperglycemia. RESULTS: 950 patients were admitted with hyperglycemia, 133 of which met criteria for hyperglycemic crisis. There was no significant difference in the frequency of cocaine use in individuals with non-emergent hyperglycemia compared to individuals with hyperglycemic crisis (16.9% vs. 17.2%, p = 0.90). 16.9% of patients with DKA, 16.4% of patients with HHS, and 6.4% of patients with HK were cocaine users. CONCLUSIONS: We found no association between active cocaine use at the time of hospital admission and development of hyperglycemic crisis, when compared to non-emergent hyperglycemia. The role of routine screening for cocaine use in patients with hyperglycemic crisis is unclear.