Hyperkalemia is not acidosis, but during acidosis, the hydrogen ions of the gastric fluid within cells enter the cells, causing the potassium ions inside the cells to move to the extracellular fluid, resulting in hyperkalemia. Clinically, it is commonly seen in organic acidosis, lactic acidosis, diabetic ketoacidosis, and acute renal failure causing acidosis. Once hyperkalemia occurs and is diagnosed, immediate treatment should be administered. First, the primary disease should be treated; next, serum potassium should be reduced. In particularly severe cases, bedside hemofiltration can be administered, and the cardiotoxic effects of hyperkalemia should be mitigated.