Sodium Hyponatremia is a condition that occurs when the level of sodium in the blood is too low..Congestive heart failure and certain diseases affecting the kidneys or liver can cause fluids to accumulate in your body, which dilutes the sodium in your body, lowering the overall level. In acute hyponatremia, sodium levels drop rapidly resulting in potentially dangerous effects, such as rapid brain swelling, which can result in a coma and death With this condition, the body holds onto too much water. This dilutes the amount of sodium in the blood and causes levels to be low.Severe hyponatremia occurs when