When do drug tests start?

Hello I am new to the recreational therapy world I just switched majors at ASU from psych. As I’m starting my junior year I am wondering does drug testing start with the practicum? I see asu has a practicum through the VA and I’m wondering if they drug test? And then I’m sure again with internship and full time there will be testing. I deal with a lot of chronic health issues and have my medical marijuana card so I’m trying to push quitting as much as possible as it helps with my pain a lot. Any advice welcome and appreciated!!