Question

Aldosterone antagonists are one class of drug commonly used for treating high blood pressure (by blocking the actions of aldosterone). Because of their actions on the P cells, which of the following would be a likely side effect of aldosterone antagonists?

hyperkalemia (too much potassium in the blood)

hypokalemia (too little potassium in the blood)

hypernatremia (too much sodium in the blood)

Answer 1

Hyperkalemia (too much potassium in the blood)

Aldosterone promotes sodium and water retention. It does so by inducing the synthesis of proteins that make up the Na+,K+-ATPase pump. These pump reabsorb sodium at the cost of potassium. Potassium is then excreted along with urine. Aldosterone antagonists block the action of aldosterone, hence they promote sodium excretion and potassium retention. Hence, hyperkalemia is a side effect associated with aldosterone antagonists.