Etc1007

I am interested in becoming a Nurse Practitioner but because my B.S is in a non-nursing field (Anthropology), I keep being directed by advisors to consider the entry-level MSN program with a Clinical Nurse Specialist track. I am only interested in an MSN program with a Nurse Practitioner track because I am interested in the treatment and dignosing of patients and would like the freedom to write prescriptions to patients. I know I will have to obtain an R.N at some point. My question is, can one become a Nurse Practitioner with only an R.N and a B.S? Or would I be required to go back for a second bachelor's degree to obtain the B.S.N? If I do have to have a B.S.N, then should I avoid going to an associates program and just head straight into a 4 year university to get the B.S.N? The problem is I hear it's difficult for post-bacc's to be accepted into a B.S.N program. Thank you in advnace for any clarification you can give me.