What are the causes of hypokalemia (low potassium levels)?

From the Guidelines

Hypokalemia is most commonly caused by excessive potassium loss through the kidneys due to diuretic medications, vomiting, diarrhea, and excessive sweating, as well as certain medications and endocrine disorders, such as primary aldosteronism, which can be identified by spontaneous or diuretic-induced hypokalaemia 1. The most frequent causes of hypokalemia include:

• Excessive potassium loss through the kidneys due to diuretic medications (especially thiazides and loop diuretics like furosemide) 1
• Vomiting, diarrhea, and excessive sweating
• Certain medications, such as insulin, beta-agonists (like albuterol), and amphotericin B
• Endocrine disorders, such as Cushing's syndrome, hyperaldosteronism, and Bartter syndrome, which can lead to increased renal potassium excretion 1
• Inadequate dietary intake alone rarely causes hypokalemia but can worsen existing deficiencies
• Alkalosis (both metabolic and respiratory) can drive potassium into cells, lowering serum levels
• Magnesium deficiency often accompanies and exacerbates hypokalemia by impairing potassium retention Rare causes of hypokalemia include renal tubular acidosis, genetic disorders, and certain toxins. It is essential to note that hypokalemia occurs because potassium is primarily an intracellular ion, and these conditions either cause excessive loss or shift potassium from the extracellular to intracellular space, reducing serum levels and potentially causing symptoms like muscle weakness, cardiac arrhythmias, and constipation. In clinical practice, it is crucial to consider the potential causes of hypokalemia and to monitor serum potassium levels, especially in patients taking diuretic medications or with underlying kidney disease 1.

From the Research

Causes of Hypokalemia

• Insufficient dietary intake of potassium 2
• Gastrointestinal potassium losses, including:
  • Vomiting 2
  • Fistulas 2
  • Malabsorption 2
  • Abuse of laxatives 2
  • Diarrhea 2
• Renal potassium losses, including:
  • Primary and secondary hyperaldosteronism 2
  • Cushing's syndrome 2
  • Intake of licorice 2
  • Diabetic coma 2
  • Renal disease 2
  • Diuretic treatment 2
  • L-dopa treatment 2
• Endocrine causes, although the specific endocrine causes are not detailed in the provided studies, it is mentioned that hypokalemia can have various endocrine causes 3

Clinical Presentation

• General and unspecific symptoms, such as:
  • Tiredness 2
  • Lack of concentration 2
  • Lack of appetite 2
  • Vomiting 2
• Symptoms from the heart, kidneys, and skeletal muscle 2