Hypokalemia is a metabolic imbalance in which there is too little potassium in the blood. Potassium is a mineral necessary for the healthy functioning of nerve and muscle cells. As with other vital minerals, potassium must remain at a normal level in order for the body to function properly. It is dangerous for the potassium level to be too high or too low.

Normally, the kidneys regulate the body's concentration of potassium through urine excretion, aided by hormones such as aldosterone and insulin. When there is a dysfunction in this process, for example when excessive sweating or urination occurs without potassium replacement, hypokalemia occurs. Hypokalemia is often a consequence of dehydration.

Causes of Hypokalemia

There are many disease processes and several medications which may cause an individual's potassium level to fall below normal limits. These may include:

  • Cushing's disease
  • Diabetes
  • Diseases of the endocrine system
  • Diarrhea
  • Eating disorders
  • Excessive sweating
  • Magnesium deficiency
  • Repeated vomiting
  • Certain antibiotics, including penicillin

Excessive use of laxatives or diuretics may cause potassium levels to drop, resulting in hypokalemia.

Symptoms of Hypokalemia

While a minor drop in potassium levels is not serious, a major drop may be life-threatening. Symptoms of hypokalemia may include the following:

  • Abnormal heart rhythms, particularly in heart patients
  • Constipation
  • Fatigue
  • Muscle damage, weakness, or spasms

A large drop in potassium level may slow the heartbeat and cause a person to feel lightheaded or faint.

Diagnosis of Hypokalemia

Since the symptoms of hypokalemia mirror those of several other conditions, accurate diagnosis is important. In order to evaluate whether a patient is suffering from hypokalemia, a physical examination is performed as well as blood tests and an electrocardiogram (EKG). In addition to a complete blood count (CBC), a metabolic panel is performed to check the levels of glucose, various minerals and proteins in the blood. A test to check hormonal levels and one to assess arterial blood gas may also be needed. An EKG checks for heartbeat irregularities and evaluates the muscle of the heart for enlargement, inflammation or damage.

Treatment of Hypokalemia

A mild case of hypokalemia is treated with potassium supplements. Such supplements are usually taken orally. For a patient with a more severe case of hypokalemia, the doctor may administer potassium by injection. In cases where the hypokalemia appears to result from diuretic usage which is still necessary, the doctor may change the patient's prescribed diuretic to a type that helps the body retain potassium. One dangerous variety of hypokalemia that can cause paralysis, results from too high a level of thyroid hormone in the blood. In such cases, treatment focuses of lowering the level of thyroid hormone and raising the level of potassium in the blood.

Complications of Hypokalemia

Under most circumstances, hypokalemia is brought under control easily through the use of potassium supplements. In cases that progress without appropriate treatment, however, potassium levels may drop to dangerous levels. In such cases hypokalemia may result in serious, even fatal, heart complications. If hypokalemia is left untreated, the condition may also lead to kidney damage.

Additional Resources