Severe Hypoglycemia from Patient Misuse of Insulin Glargine Pen

Abstract

Objective: To report a case of severe hypoglycemia resulting from a patient's misuse of an insulin glargine pen. Case Summary: A 61-year-old male with a history of diabetes mellitus type 2 (T2DM), obesity, hypertension, end-stage renal disease, and systolic heart failure was admitted to the emergency department (ED) for severe hypoglycemia. The patient's treatment was recently switched from insulin glargine to an insulin glargine pen and had mistakenly injected the entire insulin pen. He was found lethargic and unresponsive at home and was brought into the ED with an initial blood glucose level of 11 mg/dL. He was given 6 ampules of dextrose 50% in the ED, started on a dextrose 10% infusion and was subsequently transferred to the medical intensive care unit (MICU). Throughout his stay in the MICU, the patient received a dextrose 20% infusion and a total of 11 ampules of dextrose 50% to keep his blood glucose level above 100 mg/dL. After a 6-day hospital course, the patient was stabilized and was discharged on sitagliptin. Discussion: The concern for hypoglycemia is present for any patient receiving insulin therapy. A MEDLINE search revealed the rates of hypoglycemia from insulin glargine but we found no previously described cases of severe hypoglycemia due to patient misuse of an insulin glargine pen. Our patient mistakenly injected the entire contents of the pen and became unresponsive and severely hypoglycemic. The long duration properties of insulin glargine likely prolonged the patient's hospital course. According to the Naranjo scale, the adverse reaction experienced by our patient was highly probable. Conclusions: Medication changes can be confusing for patients, and pharmacists have a unique opportunity to counsel and educate patients on the proper use of their medications, thus helping to prevent adverse events such as hypoglycemia from improper use of an insulin glargine pen.