In Addison's disease with dehydration, which electrolyte abnormality is a concern?

• A. Hypokalemia
• B. Hyperkalemia
• C. Hypercalcemia
• D. Hypomagnesemia

Answer: (B)

Aldosterone deficiency in Addison's disease reduces potassium excretion in the distal nephron, so potassium backs up in the bloodstream. With dehydration, reduced renal perfusion and ongoing impairments in potassium handling compound this effect, making hyperkalemia the main electrolyte concern. Hyponatremia and volume depletion commonly accompany this condition, and acidosis can accompany the potassium shift, reinforcing hyperkalemia. In contrast, hypokalemia would occur with too much aldosterone or diuretic use; hypercalcemia or hypomagnesemia are not the typical issues driven by primary adrenal insufficiency.