There is no need to give extra water to the infant

Unless the baby is sick and is ordered by the doctor to take extra water for proventing dehydration, you do not need to give water the infant at all, the breast milk and infant formulas(if you follow the instruction of water amount should be added) contains 85% water and it is enough for the infant.

If baby takes too much water, it could lead to water intoxication in the baby. In severe cases, water intoxication can cause low blood sodium levels, irritability, coma, and even permanent brain damage.

If you feel that your baby need more water, discuss with the doctor.