What are the potential drug interactions that must be considered when co-administering ACE Inhibitors with potassium-sparing diuretics?

Co-administration of Angiotensin-Converting Enzyme (ACE) Inhibitors with potassium-sparing diuretics can lead to significant interactions. ACE Inhibitors reduce blood pressure by preventing the conversion of angiotensin I to angiotensin II, which lowers aldosterone production, and thus, decreases sodium and water retention. Potassium-sparing diuretics such as spironolactone or eplerenone act by antagonizing the effects of aldosterone at the distal renal tubules, leading to reduced sodium reabsorption and potassium excretion.

This combination may result in hyperkalemia (elevated potassium in the blood), as both medications promote increased potassium levels. Hyperkalemia can be life-threatening, leading to serious cardiac arrhythmias. Regular monitoring of serum potassium levels is recommended when these drugs are used concomitantly. Physicians must be cautious and adjust dosages accordingly or provide alternative therapy to avoid this interaction.