I was on Concerta from late 5th Grade when I was incorrectly diagnosed with ADHD until 8th Grade when I started skipping off it. That was the point where I realised I was being fed untested chemicals without my consent. That, and I started getting a listless, anxious feeling when I took. I'm off it now. That's my experience with Concerta.
Note: I'm 15. I should put that in my sig.
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I prefer to believe that the universe is fundamentally absurd, and if I ignore it, it might go away.
Never assume everyone's better off than you, that's unfounded optimism.
15 and diagnosed with Asperger's Syndrome