Which electrolyte imbalance is most commonly associated with confusion and seizures in a patient with hyponatremia?

• A. Hypernatremia
• B. Hyponatremia
• C. Hypokalemia
• D. Hypocalcemia

Answer: (B)

Low serum sodium lowers extracellular osmolality, so water shifts into brain cells and causes cerebral edema. That swelling disrupts neuronal signaling and commonly leads to confusion, with seizures possible in more severe or rapid drops. In this context, the electrolyte imbalance most linked to these CNS symptoms is hyponatremia itself. Hypernatremia tends to produce brain dehydration, while hypocalcemia can cause seizures through a different mechanism but is not the typical accompanying imbalance with hyponatremia’s neurologic presentation; hypokalemia mainly affects muscles and the heart rather than causing the CNS effects described here.