I was diagnosed when I was younger with ADD, but it was never treated. When I turned 18 I decided to take meds. I started on the low dose (18mg) of Concerta, but recently they upped my dose to 36mg. Now when I take them I feel ill. I'm dizzy and feel like vomiting. My doctor told me that the meds were supposed to help me sleep but it's been doing the opposite. I am often up till 1 or 2 in the morning. I told one of my roommates that I'm not going to take them anymore, but she said it's probably best to continue taking them until I see my doctor again. However, I don't see my doctor until after thanksgiving (Canadian). I just would like to know from people who have the diagnosis as well and who have experience with the medication on what to do? Should I continue to take them, or are there other alternatives?