Background: Hypoglycemia is the main limitation for the achievement of glycemic goals in the treatment of diabetes. Aim: To assess the incidence of hypoglycemia in an emergency department. To characterize and identify which patients are at higher risk of having it. Material and Methods: We reviewed the electronic records of patients discharged from an adult emergency room with the diagnosis of hypoglycemia between May 2011 and December 2014. Age, sex, diagnosis of diabetes (DM), antidiabetic therapy, glycosylated hemoglobin, creatinine, destination at time of discharge, blood glucose, impairment of conscience, treatment of the event and predictions were recorded. Results: Of 175,244 attentions analyzed, 251 in patients aged 69 +/- 17 years (54% women) consulted for hypoglycemia (0.14%). Eighty one percent had a type 2 diabetes, 6% a type 1 diabetes and 12% were non-diabetic. Mean blood glucose was 44.1 mg/dl. In diabetic patients, mean glycosylated hemoglobin was 6.5%. Ninety seven percent had impairment of conscience and 77% were admitted to the hospital. Among patients without diabetes, the main comorbidity was the history of a gastric bypass surgery. In type 2 diabetes, glibenclamide used alone or with other medications was involved in 59% of the events, 87% of patients were older than 65 years with a mean glycosylated hemoglobin of 6.3% and 32% had renal failure. Conclusions: The incidence of hypoglycemia was low. There were a significant number of events in older patients with type 2 diabetes mellitus and renal failure, who were treated with glibenclamide. Most of these patients had a glycosylated hemoglobin below accepted recommendations.