How should hyponatremia be corrected to minimize osmotic demyelination risk?

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Correcting hyponatremia gradually is the safest way to minimize the risk of osmotic demyelination. When hyponatremia develops gradually, brain cells adapt by lowering their osmolytes to reduce cerebral edema. If you raise the serum sodium too quickly, the extracellular environment becomes suddenly hypertonic relative to the brain cells, drawing water out of those cells too fast and damaging myelin, especially in the pons. The practical goal is to modestly raise sodium: about 4-6 mEq/L in the first 24 hours, and not more than roughly 8-12 mEq/L in the first 24-48 hours, with adjustments based on the patient’s symptoms and ongoing losses. If there’s a risk of overcorrection, interventions like desmopressin can help stabilize the rate. In contrast, correcting too rapidly increases the risk of osmotic demyelination, while not correcting at all or only treating the underlying cause without addressing the sodium level may leave the patient vulnerable to ongoing neurologic complications.