I would ask your pediatrician before giving any supplements.

I gave my daughter this (it's called d-vi-sol). I was not aware that I had to give her these drops until I read it was recommended in one of my books. The health nurse came to my house a few days after her birth and also suggested them, since she was exclusively breast fed. It is a relatively new thing so your mother or other mothers may not know of them. I only gave her them for the first four months, especially since we didn't venture outdoors a lot (she was born in january). Ask your doctor, of course, but it is recommended nowadays.