Why does acidosis cause hypokalemia?

Acidosis leads to hypokalemia primarily because when acidic substances increase in the body, hydrogen ions from the extracellular fluid enter cells in exchange for potassium ions. At the same time, the kidneys excrete more acid, increasing potassium excretion, and this dual effect reduces blood potassium concentration. If symptoms of hypokalemia such as fatigue or arrhythmia occur, prompt medical attention is recommended.

When acidosis occurs, the concentration of hydrogen ions in the extracellular fluid rises. To maintain ionic balance across cell membranes, hydrogen ions enter cells while intracellular potassium ions move out into the extracellular space. However, the kidneys subsequently activate compensatory mechanisms: to excrete excess hydrogen ions, renal tubular epithelial cells enhance sodium-potassium exchange, resulting in increased urinary excretion of potassium ions.

In addition, under acidic conditions, the distal renal tubules secrete more ammonia to bind hydrogen ions into ammonium salts for excretion, a process that indirectly promotes potassium secretion and loss. Although the initial shift of potassium out of cells may temporarily maintain normal or even slightly elevated serum potassium levels, sustained renal potassium excretion eventually leads to decreased blood potassium concentrations, causing hypokalemia.

In daily life, maintaining a regular diet with adequate intake of potassium-rich foods such as bananas and spinach is important. Avoid excessive dieting or long-term use of medications that may disrupt acid-base balance, and engage in moderate exercise to enhance metabolic regulation and maintain stable electrolyte levels in the body.