Hypernatremia is a critical electrolyte disorder characterized by elevated sodium levels in the blood, often resulting from imbalances involving water and sodium loss or gain. It is essential for healthcare professionals, particularly nurses preparing for the NCLEX exam, to understand the distinctions among the three main types: euvolemic, hypervolemic, and hypovolemic hypernatremia. Euvolemic hypernatremia occurs when total body water decreases but sodium content remains relatively stable, typically due to inadequate water intake or insensible water loss. The patient appears to have normal blood volume but elevated serum sodium concentration. Management involves free water administration, preferably orally, to replenish deficits based on the calculated free water deficit. Identifying and discontinuing the causative agent is vital to prevent progression. Hypervolemic hypernatremia, though less common, involves an increase in both sodium and water, with sodium rising disproportionately. This scenario may be due to excessive intake or retention of sodium, such as in situations involving aldosterone excess or administration of hypertonic saline solutions (e.g., 3% saline). Treatment typically includes the use of loop diuretics to enhance sodium excretion alongside free water administration to correct the hypernatremia safely. Hypovolemic hypernatremia arises from losses of both sodium and water, with water loss exceeding sodium loss—common causes include gastrointestinal losses, diuretics, or renal disease. Treatment is guided by isotonic intravenous fluids, such as normal saline initially, shifting to hypotonic fluids for gradual correction after volume status stabilization. The intravenous fluid choice is based on the judgement that normal saline is relatively hypotonic compared to hypernatremic serum. A critical aspect of hypernatremia management is the slow correction of sodium levels to prevent cerebral edema, a serious complication resulting from rapid shifts in serum osmolality that can cause brain swelling. Continuous monitoring of neurological status during therapy is mandatory. In addition to the clinical management strategies, it is important for nursing students and practitioners to focus on detailed patient assessments and individualized treatment plans based on the underlying pathophysiology. The NCLEX® exam emphasizes not only knowledge of these medical details but also the application of preventive and corrective nursing interventions to enhance patient safety and outcomes. In summary, understanding the pathophysiology and treatment protocols for each type of hypernatremia helps optimize patient care. Healthcare providers should prioritize slow correction with appropriate fluid administration based on the type of hypernatremia and monitor neurological signs vigilantly to avoid life-threatening complications.