My daughter is 10 and was diagnosed with ADHD combined type at 5 years old. However, her symptoms never fully fit the diagnosis and she had many other symptoms that weren't being captured fully under the ADHD umbrella. She was medicated for a few months with Focalin XR. She never had improvement of inattention symptoms with medication, and she was very agitated and irritable while taking it. She was later diagnosed with Asperger's Syndrome. I think both diagnoses have an executive dysfunction as part of their core symptoms. I think the reasons for inattention come from a different place for ADD or ADHD vs. Asperger's. ADD or ADHD kids are distracted by external stimuli and have trouble focusing in noisy classrooms. I think kids with Asperger's are more internally focused and thus inattentive (as in lost in their own thoughts). As someone with a child with Asperger's, I can tell you that ADHD medication is hit or miss with autistic kids for this reason. It will either help them or make their symptoms worse. I do see a lot of improvement with focusing on organizational skills, use of routines, and lists. I find that if I make a list for a task and hand that to her, she will complete it every time. Also, she tends to not be focused on time or completing tasks in a timely manner. I try to use a stopwatch and give her time prompts like "five more minutes" to keep her moving. This is really a struggle. If your son does have Apserger's, and not ADHD, medication is not likely to be a treatment option for you. You may have to focus on behavior modification and improving organizational skills.

Good Luck!