Low blood potassium is also known as hypokalemia. The causes of the disease are mainly insufficient intake and excessive excretion. If left untreated, it may cause dyspnea, respiratory failure, low blood pressure, cardiac arrhythmia and so on. It is recommended to consult the doctor in time and treat the disease after the cause is clarified under the doctor’s guidance. 1. Etiology: Serum potassium is lower than the minimum concentration of normal physiology due to various reasons, usually blood potassium is lower than 3.5mmmol/L. Etiological causes include prolonged insufficient intake, such as starvation, coma, prolonged fasting after surgery, gastrointestinal obstruction, esophageal cancer leading to difficulty in eating, etc., which may cause symptoms of low blood potassium. Secondly, excessive discharge, such as vomiting, diarrhea, gastrointestinal drainage, intestinal fistula, etc., may lead to a large amount of loss of potassium ions, thus causing symptoms of low potassium concentration. 2. Harm: After the blood potassium is lowered, if not treated in time, malignant cardiac arrhythmia and respiratory muscle paralysis may occur, resulting in dyspnea, heart failure, arrhythmia, ventricular fibrillation, convulsions, cardiac arrest, etc., which may cause very serious harm to health. Oral potassium chloride, potassium citrate, potassium glutamate and other drugs can be taken as prescribed by the doctor for potassium supplementation treatment.