Which condition is characterized by confusion and seizures due to low sodium levels?

Hyponatremia is a condition that occurs when the sodium levels in the blood fall below the normal range (typically less than 135 mEq/L). Sodium is crucial for maintaining normal nerve and muscle function, as well as for regulating fluid balance in the body. When sodium levels are low, it can lead to an imbalance in osmotic pressure, causing water to move into cells, including brain cells. This cellular swelling can result in neurological symptoms such as confusion and seizures, among other complications.

In the context of the other conditions mentioned, hypernatremia refers to high sodium levels, which can lead to symptoms such as thirst, confusion, and agitation but not the specific issues stemming from low sodium. Hypocalcemia and hypercalcemia relate to calcium levels in the body, which affect muscle and nerve function differently and are not typically associated with the confusion and seizures seen in hyponatremia. Thus, the specific characteristics of confusion and seizures due to low sodium levels align directly with hyponatremia.