Treatment of liver hydatid cysts is still in most cases surgical. To avoid the recurrence of hydatid cysts injection of scolicidal products inside the cystic cavity is an important step in the surgical procedure. Many scolicidal solutions are used. Hypertonic Saline Solution (HSS) is widely used by surgeons; however, there is a risk of hypertonic saline resorption and acute hypernatremia. Iatrogenic hypernatremia can be life-threatening. We report three cases of hypernatremia secondary to HSS injection for hydatid cyst disease treatment. The objective of this study was to discuss the clinical features, and treatment of this rare complication.