Hypokalemia has diverse clinical manifestations. The most life-threatening symptoms involve the cardiac conduction system and the neuromuscular system. In mild hypokalemia, the electrocardiogram (ECG) shows flattened T waves or their disappearance, along with the appearance of U waves. Severe hypokalemia can lead to lethal arrhythmias, such as ventricular tachycardia, ventricular fibrillation, or sudden death. In the neuromuscular system, the most prominent symptoms of hypokalemia are in the skeletal muscle, presenting as sluggish paralysis and loss of tone in the smooth muscle, leading to rhabdomyolysis. If respiratory muscles are affected, it may result in respiratory failure. Hypokalemia can also cause insulin resistance and obstruct insulin release, leading to significant glucose tolerance abnormalities. Decreased potassium excretion reduces the kidney's ability to concentrate urine, resulting in polyuria.