What are the common causes of hyperkalemia?

Hyperkalemia, which is an elevated level of potassium in the blood, can be attributed to several underlying conditions, with renal failure and tissue breakdown being among the most common causes. When the kidneys are not functioning properly, they are unable to excrete potassium effectively, leading to its accumulation in the bloodstream. This is particularly important in chronic kidney disease or acute kidney injury, where renal function is compromised.

Tissue breakdown, or the release of potassium from cells, can also contribute to hyperkalemia. Conditions such as trauma, burns, or hemolysis cause cells to release their stored potassium into the extracellular space, increasing blood potassium levels.

Other options listed do not typically lead to hyperkalemia. For example, excessive calcium intake does not directly affect potassium levels, high sodium consumption does not cause hyperkalemia but can influence blood pressure and fluid balance, and although dehydration can affect electrolyte concentrations, it is not a direct cause of hyperkalemia. Instead, dehydration often leads to more concentrated levels of potassium rather than an actual increase in total body potassium. Thus, renal failure and tissue breakdown are the key contributors to hyperkalemia.