About Low Potassium Levels

Potassium is essential for life; it facilitates the function of cell membranes, nerve impulses and muscles--including the heart. A low potassium level, or hypokalemia, causes a variety of symptoms and in severe cases is life-threatening. Although potassium is obtained from diet, low potassium is rarely caused by dietary deficiencies. Most people get considerably more potassium from their diet than strictly necessary; the excess is excreted in the urine.

Identification

• Low potassium levels are diagnosed by performing a serum potassium test. This is a blood test performed at a doctor's office, hospital or medical lab. A vial of venous blood is drawn, and the level of potassium is measured by lab personnel. Since many drugs can interfere with the accuracy of this test, it is important to inform your doctor about any medications you are taking. This test is usually performed only when hypokalemia is suspected based on your risk factors or symptoms.

Significance

• Most cases of low potassium levels are a result of major fluid losses, such as severe vomiting, diarrhea or extremely heavy sweating. Potassium loss is also a side effect of certain medications, especially diuretics. Occasionally, hypokalemia points to an underlying disorder, such as severe undiagnosed diabetes, an adrenal tumor or a rare hereditary disorder.

Effects

• Slightly low potassium levels rarely cause symptoms, although blood pressure may be mildly elevated. More severe cases cause muscular problems such as weakness, cramps, aches, paralysis and involuntary muscle contractions. Heart function may be impaired by moderate or severe hypokalemia, which can cause abnormal electrocardiogram, or ECG, findings, arrhythmias and cardiac arrest.

Prevention/Solution

• Treatments for low potassium levels focus on two areas--treating the cause of potassium loss and replacing the lost potassium. Treatment for the cause of the hypokalemia varies depending on whether a medication, serious illness or underlying disorder is at fault. Potassium replacements may be taken at home or in a hospital, depending on the severity of the hypokalemia. In mild to moderate cases, oral potassium replacement is usually prescribed; this is usually a white liquid that is mixed into juice or another drink to mask the taste. Intravenous potassium is necessary for severe hypokalemia, and this treatment is always administered in a hospital while the patient's heart is monitored continuously for abnormalities.

Warning

• Low potassium levels can be deadly. If you have impaired kidney function, poorly controlled diabetes or are taking medication that may cause potassium loss, it is important to have regular blood tests to monitor your serum potassium level. Your doctor may also want to test your potassium level if you have recently experienced severe vomiting or diarrhea, or if you have an eating disorder. These conditions may sometimes lead to life-threatening hypokalemia.