Generally speaking, the causes of low blood potassium are diverse and can be summarized in three main areas: insufficient potassium absorption or intake, excessive potassium loss and extracellular movement of intracellular potassium. Insufficient absorption or intake of potassium in the body. This is often seen in patients who are anorexic, picky eaters, malnourished and have an unbalanced diet. In addition, patients with certain gastrointestinal disorders may also develop hypokalemia due to restricted food intake. Second, excessive potassium loss. Clinically, patients with severe diarrhea and vomiting, severe burns, infections and certain wasting diseases, shock, etc., may lead to low potassium levels in the patient’s body. In addition, certain food or drug poisoning may also cause the patient’s blood potassium to be lower than normal. Third, intracellular potassium moves outside the cell. For example, some patients with hypokalemic periodic paralysis often have intracellular potassium move outside the cell during disease episodes, which can cause hypokalemia. Fourth, some diseases, such as primary aldosteronism, can cause increased urinary potassium elimination, thus causing hypokalemia and hypertension to be seen together. Fifth, the application of insulin in some diabetic patients may also cause a shift of potassium ions from extracellular to intracellular, resulting in hypokalemia. Thus, to summarize the causes of hypokalemia, the main causes include insufficient absorption or intake of potassium, excessive potassium loss, and a shift of extracellular potassium to intracellular.