How long does it take to become a substance abuse nurse if you haven't started nursing school?

Depends. Nursing degrees span the educational spectrum. From two year LPN progams to 3 year rn training, to 4 year bsn (bachelors degree), 6 year master's degree programs (msn), to 8 year nurse practitioner programs. These are great fields and have abundant opportunities for success, advancement and being socially redeeming. To do alcohol & drug treatment, you'll need another two years.