Water intoxication, also known as dilutional hyponatremia, occurs less frequently in the clinic and refers to a situation in which the total amount of water ingested by the body exceeds the amount of water excreted, so that water is retained in the body, causing a decrease in plasma osmolality and an increase in circulating blood volume. Symptoms such as increased intracranial pressure, psychoneurological manifestations, and increased extracellular fluid may occur. 1. Increased intracranial pressure: due to the edema of brain cells, the intracranial pressure increases, blurred vision, fatigue and other symptoms can occur. 2. Psychoneurological manifestations: When the serum sodium concentration falls below 120 mmol/L, it may damage the central nervous system, and thus the patient may experience symptoms such as confusion, disorientation, delirium, and epileptiform seizures. 3. Increased extracellular fluid: Due to water retention, the extracellular fluid volume increases, which may be accompanied by pulmonary edema as well as increased salivary and tear secretion. In addition, it is recommended that patients with dilutional hyponatremia go to the hospital in time to avoid delay.