The total amount of potassium stored in the body is about 3000 mEq (50-70 mEq/kg body weight), concentrated mainly in the cells (140 mEq/L). In blood and extracellular fluid, normal potassium levels are 3.5–5 mEq/L. That is the value of potassium measured in a blood test. Hypokalemia is considered to be decreased when the serum potassium level is <3.5 mEg/L (mmol/l). Blood potassium is considered elevated when the serum potassium level is >5 mEq/L (mmol/l). Regulates potassium levels in the body through two processes: intracellular potassium exchange - extracellular fluid and renal excretion of potassium.