[michael8i]

I have been a nurse for nearly twenty years.

I would advise your son to pursue medical school if at all possible.

He will be respected and will not undergo so much difficulty and will still be able to fulfill his goals to help people.

[GratefulTedd]

long term growth of income/income potential over the course of a career is my only reservation. other professions tend to reward more senior employees better (assuming you don't get down-sized first), both financially and general regard in the community. there's job security in nursing- currently the shortage makes getting a job nearly a sure thing.
I see discrimination daily towards men in nursing- but it is subtle and easily dealt with (such as answering the phone and hearing someone say hesitantly "oh, sorry, I was looking for my mother's nurse" -thats me- "oh, ok, well...how is she doing then?").
have him research all his options and decide- up to him.