Potassium supplementation needs to be accompanied by magnesium supplementation. Hypokalemia needs to be treated with potassium supplementation, but magnesium supplementation is also needed to promote the transfer of potassium ions into the cells, thus increasing the therapeutic effect. The concentration of potassium ions inside the cell is significantly higher than that outside the cell, and the transfer of potassium ions from outside the cell to the cell needs to be carried out with the help of the sodium-potassium pump on the cell membrane, and the sodium-potassium pump can transfer 3 sodium ions to the outside of the cell and 2 potassium ions to the inside of the cell by consuming 1 molecule of ATP (adenosine triphosphate). And magnesium ion is an important substance to activate the sodium-potassium pump on the cell membrane, so magnesium ion can promote the absorption of potassium ion. When magnesium is deficient, the function of sodium-potassium pump will be significantly weakened, the supplemental potassium ions can not be transferred to the cell, the function of the kidney to preserve potassium is weakened, which leads to the loss of a large amount of potassium in the urine, so there will be a situation in which how to replenish the blood potassium can not be replenished. Supplementation of magnesium is also needed along with potassium supplementation, while changes in urine output and blood potassium need to be closely monitored to avoid excessive blood potassium.