Excellent point. ADD sufferers often try to medicate themselves. I have had ADD symptoms all my life. I compensated by drinking excessive amounts of caffeine at work and maintaining a rigid exercise schedule.
Just recently, I started taking small doses of Ritalin (5-10 mg per day) and I have had remarkable results. I keep the dosages low because I also have addictive disorders running in my family and I am worried about the long term effects. Just a small amount helps me get stated in the morning. ADD sufferers have problems starting projects. So I find once I get going on something in the morning I can usually keep on it in the afternoon.

Overall I have better concentration, a more positive attitude and feel much more relaxed. I hardly touch caffeine anymore and I am sleeping better than ever. So all in all it has been a positive experience for me.