I wonder. Before I got diagnosed with ADD, I drank tea and soda with caffeine without worry that it would keep me awake. I drank like 10 cups of tea and / or caffeinated soda a day. Now since I started focalin xr for ADD, I must drink decaffeinated tea or soda. I feel anxious on those days if I drink the caffeine drinks. On the days I skip the focalin xr, I can drink caffeinated tea and soda and again there are no anxiety problems or problems with it keeping me awake at night. I don't quite get it.