Hyponatremia is a prevalent electrolyte imbalance disorder, and it results in the syndrome of inappropriate antidiuretic hormone secretion (SIADH) in approximately one-third of all cases. To diagnose SIADH, it is crucial to confirm the normal volume of extracellular fluid by conducting clinical examinations and laboratory tests. Treatment of SIADH is essential to relieve symptoms, although the clinical role and treatment conditions for mild to moderate symptoms are unclear. Non-specific measures are available for treating SIADH, including fluid restriction, hypertonic saline, urea, and demeclocycline. Fluid restriction and hypertonic saline are the most commonly used options.