Introduction ACE inhibitors (Angiotensin-Converting Enzyme inhibitors) and potassium-sparing diuretics are frequently prescribed for conditions like hypertension, heart failure, and chronic kidney disease. Each drug class offers substantial therapeutic benefits; however, their combined use carries a serious risk—hyperkalemia, or elevated potassium levels in the blood. While this combination can be beneficial for select patients, the interaction requires vigilant clinical oversight due to its potential to cause life-threatening complications, such as cardiac arrhythmias. Why Hyperkalemia Occurs Hyperkalemia is defined as a serum potassium level above 5.0 mmol/L. It becomes clinically significant when levels rise above 5.5 mmol/L and potentially dangerous above 6.0…