Common causes of hypokalemia include insufficient intake or prolonged inability to eat without intravenous supplementation. In such cases, while intake of potassium decreases, the kidneys continue to excrete potassium, leading to a loss of potassium in the blood. Additionally, increased excretion can cause hypokalemia, including losses from the gastrointestinal tract such as vomiting, diarrhea, and continuous gastrointestinal decompression, which results in a loss of digestive fluids rich in potassium. Potassium loss through the kidneys from prolonged use of potassium-wasting diuretics or during the polyuric phase of acute renal failure can also lead to hypokalemia. Furthermore, the shift of potassium from outside to inside the cells can cause hypokalemia.