**Question:** A patient is receiving insulin and acarbose for diabetes mellitus and developed hypoglycemia. Which of the following should be used for treatment of hypoglycemia in this patient?

A. Glucagon
B. Insulin
C. Acarbose
D. Dextrose

**Core Concept:**
Diabetes mellitus is a group of chronic diseases characterized by high blood sugar levels due to insulin deficiency, insulin resistance, or both. Acarbose is an alpha-glucosidase inhibitor used to lower blood glucose levels by blocking the digestion of carbohydrates in the gastrointestinal tract. Insulin is a hormone that lowers blood sugar levels by facilitating the absorption of glucose by cells and inhibiting hepatic glucose production. Hypoglycemia occurs when blood sugar levels fall below the normal range, which can be due to insulin overdose or insufficient counterregulatory hormone response.

**Why the Correct Answer is Right:**
In this scenario, the patient is receiving insulin therapy, which is a potent hypoglycemic agent. When insulin levels are elevated and the patient experiences hypoglycemia, the treatment should target reducing insulin levels and stimulating counterregulatory hormones to restore blood glucose to normal levels. Glucagon is a hormone that raises blood sugar levels by stimulating glycogenolysis in the liver and gluconeogenesis in the liver and kidneys. Since hypoglycemia is due to insulin overdose, administering glucagon will help correct the imbalance by stimulating glycogenolysis and gluconeogenesis.

**Why Other Options are Incorrect:**
Acarbose is an alpha-glucosidase inhibitor used for type 2 diabetes treatment to lower blood glucose levels by blocking carbohydrate digestion. Since acarbose is responsible for the elevated insulin levels and hypoglycemia, administering acarbose would worsen the condition.

**Insulin** is a potent hypoglycemic agent, which is inappropriate in this scenario as insulin overdose is causing the hypoglycemia. Administering more insulin would exacerbate the issue.

**Dextrose** is a simple sugar (monosaccharide) used to raise blood glucose levels. While dextrose is essential for treating hypoglycemia, in this context, administering dextrose alone will not address the root cause of the hypoglycemia, which is insulin overdose.

**Clinical Pearls:**
1. When treating hypoglycemia in patients on insulin therapy, it is crucial to focus on counteracting the insulin overdose. In this scenario, glucagon is the appropriate treatment choice as it targets the root cause of insulin overdose and helps restore blood glucose levels.
2. It is essential to understand the underlying cause of hypoglycemia (insulin overdose) and choose a treatment that addresses this cause rather than simply treating the symptom (low blood glucose).