Switching out of my major before the year starts.

I was recently accepted into the Nursing Program at CSUF, which is great news. However, after submitting my application in November I realized that I love teaching.
I am 100% sure I want to become a teacher, but is it possible to switch out of Nursing after accepting admission? How might I accomplish this and who should I email? Would this out my admission at risk? Should I just stay in Nursing until Sophomore year?

Contact CSUF and ask. I am sure that opening a spot for another prospective Nursing student would be very much appreciated.