From the Guidelines
Hypokalemia is most commonly caused by excessive potassium loss through the kidneys due to diuretic medications, particularly thiazides and loop diuretics like furosemide, as well as vomiting, diarrhea, and excessive sweating, as supported by the guidelines for the diagnosis and treatment of chronic heart failure 1.
Causes of Hypokalemia
The causes of hypokalemia can be categorized into several key areas:
- Excessive potassium loss through the kidneys due to diuretic medications (especially thiazides and loop diuretics like furosemide) 1
- Gastrointestinal losses such as vomiting and diarrhea
- Excessive sweating
- Certain medications like high-dose penicillins, amphotericin B, and corticosteroids that promote potassium excretion
- Endocrine disorders including hyperaldosteronism, Cushing's syndrome, and magnesium deficiency
- Inadequate dietary intake, which rarely causes hypokalemia alone but can worsen existing deficiencies
- Intracellular shifts of potassium during alkalosis, insulin administration, and beta-adrenergic stimulation (as with albuterol)
- Rare genetic disorders like Bartter and Gitelman syndromes that cause chronic hypokalemia
Clinical Significance
Recognizing these causes is crucial because untreated hypokalemia can lead to significant morbidity and mortality, including muscle weakness, cardiac arrhythmias, and in severe cases, paralysis or respiratory failure 1. The clinical signs associated with severe hypokalemia can include life-threatening ventricular arrhythmias, emphasizing the need for prompt identification and treatment of the underlying cause.
Treatment Approach
Treatment of hypokalemia depends on identifying and addressing the underlying cause while simultaneously correcting the potassium deficit through oral or intravenous supplementation. In the context of diuretic-induced hypokalemia, the use of potassium-sparing diuretics like spironolactone may be considered, especially in cases of severe heart failure or when there is persisting diuretic-induced hypokalemia despite concomitant ACE inhibitor therapy 1. However, the decision to use these medications should be made cautiously and with careful monitoring of serum creatinine and potassium levels.
From the FDA Drug Label
Hypokalemia may develop with Furosemide tablets, especially with brisk diuresis, inadequate oral electrolyte intake, when cirrhosis is present, or during concomitant use of corticosteroids, ACTH, licorice in large amounts, or prolonged use of laxatives. Hypokalemia may develop, especially with brisk diuresis when severe cirrhosis is present, during concomitant use of corticosteroid or adrenocorticotropic hormone (ACTH) or after prolonged therapy. Interference with adequate oral electrolyte intake will also contribute to hypokalemia
Causes of hypokalemia include:
- Brisk diuresis
- Inadequate oral electrolyte intake
- Presence of cirrhosis
- Concomitant use of:
- Corticosteroids
- Adrenocorticotropic hormone (ACTH)
- Licorice in large amounts
- Prolonged use of laxatives
- Corticosteroid