Why does overhydration lead to hyponatremia in renal failure patients?

💡 Explanation

In renal failure, the kidneys' ability to excrete water is compromised; therefore, overhydration causes an excessive dilution of sodium in the extracellular fluid, leading to hyponatremia, because the kidneys can't compensate. This dilution effect occurs rather than excess electrolyte concentration which is the opposite effect.

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