I am diagnosed with adult ADHD and Asperger's syndrome, and after seeing my psychiatrist today whom is a specialist in adult ASD/ADHD, I've been prescribed 'Ritalin' to help me concentrate which in turn can also reduce my anxiety levels, but I just read up about 'Ritalin' also called 'Methylphenidate' on wikipedia and it says the effects of taking it are similar to cocaine or amphetimine and that its a controlled 'class B' substance in the UK, its illegal to possess it without a prescription. Reading all this has made me very nervous about taking it as I'm due to start taking it tomorrow. Has anyone else been prescribed this and should I really be worried?