Hyponatremia is a common electrolyte disorder characterized by a low concentration of sodium in the blood, which can lead to serious neurological complications if not managed properly. Understanding the different types of hyponatremia—euvolemic, hypervolemic, and hypovolemic—is crucial for accurate diagnosis and effective treatment. Euvolemic hyponatremia occurs when the total body water increases, but the sodium content remains the same, leading to dilutional hyponatremia without significant changes in fluid volume status. Common causes include the syndrome of inappropriate antidiuretic hormone secretion (SIADH), hypothyroidism, and adrenal insufficiency. Management typically involves restricting free water intake and, in some cases, administering sodium tablets or osmotic diuretics to help restore sodium balance while maintaining normal fluid levels. Hypervolemic hyponatremia is characterized by a significant increase in total body water that dilutes sodium concentration. This condition often occurs in patients with congestive heart failure, cirrhosis, or nephrotic syndrome, where both water and sodium retention happen but water retention predominates. Treatment focuses on restricting free water, using sodium tablets or diuretics, and addressing the underlying condition to reduce excess fluid and correct sodium levels. Hypovolemic hyponatremia results from the loss of both water and sodium, but sodium loss exceeds water loss. This can be seen in cases of vomiting, diarrhea, diuretics misuse, or adrenal insufficiency. Management requires careful volume replacement with isotonic fluids such as 0.9% normal saline for mild cases and hypertonic saline for severe hyponatremia, ensuring restoration of both water and sodium while avoiding rapid correction. A critical nursing consideration across all types of hyponatremia is to monitor neurological status closely to detect symptoms like confusion, seizures, or signs of cerebral edema. Correction of sodium imbalance must be performed slowly to prevent osmotic demyelination syndrome, a serious neurological condition caused by overly rapid correction. By incorporating this detailed understanding of hyponatremia types, causes, and tailored management strategies, healthcare professionals can significantly improve patient outcomes. This knowledge is particularly vital for nursing students preparing for exams such as the Next Generation NCLEX®, providing a strong foundation for safe clinical practice.