Which laboratory abnormality is most commonly noted in bulimia nervosa?

• A. Glycosuria
• B. Hypokalemia
• C. Metabolic Acidosis
• D. Hyperalbuminemia

Answer: (B)

Frequent purging in bulimia causes loss of potassium along with gastric hydrogen ions. Vomiting and laxative use deplete potassium stores, and the accompanying volume depletion stimulates aldosterone, promoting further potassium loss in the kidneys. The net result is a low serum potassium level, making hypokalemia the most common laboratory finding in bulimia.

Glycosuria isn’t a typical finding unless another condition like diabetes is present. Metabolic acidosis would be unlikely here because vomiting leads to loss of HCl and typically causes metabolic alkalosis, not acidosis. Hyperalbuminemia isn’t expected from bulimia-related electrolyte disturbances.