People still discriminate regardless of the anti discrimination laws, it happens all the time in the medical field. I didn't get a position for a job in the medical field because when they drug tested me they found that I was taking risperdal and other prescribed meds. There really was no tangible proof that they discriminated against me, but it was obvious after the second interview and drug test.

Regarding the OP original question, it should be fine to be a therapist as long as your symptoms/illness does not affect your work ethic or your patients.