Generally, potassium supplementation can return to normal after 2-3 days, and 1-2 weeks or longer in serious conditions. Potassium is one of the essential trace elements, long-term insufficient intake, can not eat, or have severe vomiting, diarrhea patients, hyperthyroidism patients, etc. often cause hypokalemia, the patient may appear weakness, abdominal distension, muscle pain, serious cases can appear arrhythmia, respiratory muscle paralysis, life-threatening. Therefore, it is necessary to replenish potassium in time to prevent the condition from worsening. For patients with mild hypokalemia or acute potassium deficiency, blood potassium is usually supplemented for 2-3 days to return to normal. For severe hypokalemia due to hyperthyroidism or other reasons, potassium supplementation is needed for a longer period of time, usually 1-2 weeks or longer to normalize the blood potassium. In addition, for acute low potassium, it can be supplemented with fluids and can be recovered quickly. For chronic low potassium, in addition to oral potassium supplementation, dietary modification is also needed, and more fruits or vegetables with high potassium content can be eaten, such as bananas, oranges, potatoes and so on. During the period of potassium supplementation, attention should be paid to review the blood electrolytes, observe the recovery of blood potassium at any time, and adjust the dosage of potassium supplementation in time.