Excessive hydration in newborns

Excessive hydration (overhydration) in newborns

Overhydration, or water intoxication, is a rare but potentially dangerous condition that occurs when excess water accumulates in a newborn's body. This leads to a critical drop in blood sodium concentration (hyponatremia). In infants in the first months of life, this almost always happens due to caregiving errors rather than intentional excessive drinking.

Why does overhydration occur in newborns?

A small child's kidneys are still immature and cannot eliminate large amounts of water as efficiently as adult kidneys. The reasons for excess fluid intake can include:

• Improper dilution of infant formula: This is the most common cause. Parents, trying to save money or mistakenly thinking they are making the mixture "lighter", add too much water.
• Excessive water supplementation: Offering large amounts of plain water to a child under 6 months, especially in place of breast milk or formula. Newborns obtain all necessary fluid from their primary nutrition.

Mechanism of injury

The main danger, as with general overhydration, lies in the development of hyponatremia and cerebral edema. This leads to neurological symptoms: irritability, lethargy, vomiting, and in severe cases — seizures. This condition requires immediate medical attention and correction of the electrolyte balance.