My children were both diagnosed with depression and anxiety as teens. While they both continue to sometimes struggle, one of the things that has helped both the most is finding a good therapist. They have both also been treated with meds, which help, but I can't overstate the importance of therapy. Sometimes it takes a while to find the right "fit" but it's worthwhile to keep trying. I know that's challenging with a teenager, but it's worth it. Do your homework with the meds. Unfortunately, it can take time to get the right medication and dosage. Make sure you feel comfortable with the doc he's seeing and that they take the time to really talk to YOU as well as your son, and the course of therapy they suggest is something you are comfortable with. Good luck!