Severe potassium deficiency can be life-threatening. In mild hypokalemia, the patient may feel weak and uncomfortable all over the body. If the condition is further aggravated, the patient may experience bilateral lower limb weakness, feel unable to control his legs and have the feeling that he cannot move his legs, but his consciousness is normal, accompanied by perioral numbness, abdominal distension and indigestion. Further aggravation of hypokalemia may even affect the normal function of the respiratory muscles, resulting in poor breathing or complete inability to breathe, while suffering from hypoventilation. In terms of heart function, hypokalemia can be manifested as a decrease in the electrical conduction of the heart muscle, which can lead to abnormalities in the contraction of the heart muscle, and in severe cases, cardiac arrest, which can be life-threatening.