Ritalin is a mild amphetimine used to treat people with ADHD or ADD. Pending on your condition it could have either good effects or bad. If you don't actually suffer from either of those you could get bad headaches, hyperactivity, etc. I took some of my friends occasionaly in high school and it was a hit or miss situation. I usually took them before golf meets, I'd either play really well and be focused or shoot my wad and couldn't concentrate on a pair of tits if I tried.