Is nystain harmful to a baby if he was given too much. The lady at the pharmacy told me to fill the syringe up for my new baby of nystatin for his thrush. But as I was looking today I noticed the syringe says 10 ml at top so I believe he has been getting way more than prescribed

His prescription is 1 ml in each cheek I believe he's getting 20 ml in each cheek.

In the event you are serious CALL YOUR PHYSICIAN IMMEDIATELY.