The muscles, nerves and cells in the body need a certain level of potassium to function normally. When levels are too high or low, you are at risk for several health problems. Normal levels of potassium are 3.6 to 4.8 milliequivalents per liter, or mEq/L. When levels of potassium fall lower than normal, the condition is termed hypokalemia. Potassium levels less than 2.5 mEq/L are considered critically low, and life-threatening complications can occur.
Causes
Potassium is mostly lost through urine, the digestive tract and sweat. It is replenished by eating foods that contain potassium. Conditions that cause an excess loss of potassium include diarrhea and vomiting. Certain medical conditions, such as Cushing's syndrome might cause excess potassium loss in urine. How fast potassium moves in and out of the cells can also affect the levels in the body. Conditions such as hyperthyroidism cause potassium to move out of the cells more quickly and can lower potassium to critical levels.
Symptoms
When potassium levels become critically low, symptoms can include muscle spasms, weakness and fatigue. Muscle fibers might start to break down, and paralysis can develop. Paralysis can include the diaphragm, which interferes with the ability to breathe. One of the most serious and life-threatening symptoms of critically low potassium is an abnormal heart rhythm, which can lead to cardiac arrest.
Identification
If critically low potassium levels are suspected, a blood test will be ordered to check potassium levels. Additional blood work might also be recommended to measure the levels of other electrolytes, such as sodium. Because low potassium levels can lead to cardiac arrhythmia, an electrocardiogram will likely be done to monitor the heart's rhythm. Additional tests might be ordered to determine what condition led to low levels of potassium.
Treatment
Often critically low levels of potassium will require the administration of potassium intravenously. This allows it to get into the body faster than if administered orally. Additional treatment might include correcting abnormal heart rhythms through medications. Determining the cause of low potassium levels and treating the underlying problem are also essential.
Prevention
Eating foods rich in potassium, such as bran, tomatoes and bananas, can help keep levels balanced, but critically low levels of potassium are generally not caused by diet. Seeking prompt treatment for medical conditions that might interfere with potassium levels is also essential to prevent levels from becoming critically low.
Member Comments