I was in the same boat as you. one of the questiones on the application has to do with mental illness. I checked the box and attached a letter explaining the antidepressant I am taking, and the reasons for it. I also explained how taking the medication affects my life, and the fact that I am confident in my position, and am comfortable with where I am. Before I was approved, I was requested to have a doctor sign a medical certificate, issues by the CFO, stating that I am ok, and not crazy, or violent and stuff. After I got that paper sent in, my application was approved a few days latter.
As mentioned, honesty is key and it will only hurt your chances if you lie about and they find out.