I have a 15 year old daughter with ADHD who was diagnosed at 7. I was a stay at home mom, she always had discipline and structure, but bless her heart, she just couldn't stop moving. After two years of kindergarten, she still didn't know her alphabet--she literaly couldn't sit still long enough. She was diagnosed, and yes, given Ritalin, and she learned to read at a 1st grade level in 6 weeks. At 15, she, not me, talks to the dr about her needs and openly discusses where she feels change is needed.
While it sounds like a pat diagnosis--no discipline or environment, please remember children are complicated. My husband and I thank God that she received the help she needed in a timely manner.