Pheochromocytoma is a catecholamine-producing tumor. During attacks, what metabolic change occurs?

• A. Hypoglycemia
• B. Hyperglycemia with Glycosuria
• C. Decreased Liver Glucose Production
• D. Ketosis

Answer: (B)

During a pheochromocytoma attack, a surge of catecholamines (especially epinephrine) drives metabolic changes that raise blood glucose. Epinephrine stimulates the liver to break down glycogen and produce glucose (glycogenolysis and gluconeogenesis), while also reducing peripheral glucose utilization by tissues. At the same time, insulin secretion or action is suppressed, further tipping toward higher blood glucose. When glucose becomes elevated enough, the kidneys spill excess glucose into the urine, producing glycosuria. This pattern—hyperglycemia with glycosuria—fits the acute metabolic response to catecholamine excess. Hypoglycemia is not typical in this context, and ketosis isn’t the characteristic acute change here, since glucose production and levels rise rather than fall.