Hypokalemia refers to a condition where the serum potassium level is below 3.5 millimoles per liter. The primary cause of hypokalemia is the loss of potassium in the body. Hypokalemia can be classified into three types based on its cause: potassium deficiency hypokalemia, redistributive hypokalemia, and dilutional hypokalemia. Potassium deficiency hypokalemia is mainly characterized by insufficient intake or excessive excretion. Insufficient intake is typically seen in patients who are fasting, have selective eating habits, or suffer from anorexia, while excessive excretion is mainly through gastrointestinal or renal loss of potassium. Redistributive hypokalemia usually occurs due to metabolic or respiratory alkalosis, the recovery phase of acidosis, heavy usage of glucose, instances of periodic paralysis, acute emergency situations, and the use of folic acid and vitamin B12 in treating anemia or repeat transfusions of cold stored washed red blood cells. Dilutional hypokalemia, on the other hand, is mainly caused by the retention of extracellular fluid, leading to excessive water or water intoxication-induced hypokalemia.