Hello. My child psychologist believes along with the mainstream that no child with autism can be diagnosed with ADHD. That is because many of the symptoms are the same, but the causes are different. That being said, my pediatrician said that in practice sometimes the same medicine can help, and the only way to know is to try the medication. The best way to do it is not to let the school know you are doing it, and try it for 2 weeks or 4 weeks and then take him off and see if they notice a difference. There is a computer test that tracks the eyes of a child and it can show improvement with and without the medication, but my autistic son refused to take the test. They didn't tell him it would be a boring time -- they told him it was a game, but it was so boring-ass he couldn't stand it.
So we have been trying one ADHD medication and the school doesn't know and hasn't noticed any difference. I don't know if he needs a different medication or if he's not going to respond.
Our psychologist put in place a reward system for our son to motivate him, because autistic kids don't have the same response to more subtle rewards like praise. He is learning more and is more focused during the short bursts of learning in second grade (5 min).
But during many observations in the classroom, even our psychologist who has experience with hundreds of autistic children thought perhaps our son might need medication because even when he wanted to focus he couldn't unless he put his head on the desk or put blinders over his eyes -- attempts to make himself focus.
So, you see, it can be complicated.
My pediatrician also said that artificial dyes can increase the symptoms of both ADHD and autism, so he suggests cutting them out. I do know that in France they don't allow those dyes in M&Ms etc and their ADHD rate is only 3%.

It is not to early to get diagnosed it is common to have ADHD and ASD at the same time. We put our son on Adderall and it does wonders for him without drugging out his personality. It allows him to focus and stay calm

My daughter has PDD and adhd ...she's still hyper but not even close to when she was 5 she was bad but she's 9 now n I see a big difference but I give her meds only to go to school she does and feels so much better. ..I know what it's like to want to do what's right but your brain doesn't let you I was never diagnosed until 2 years ago I'm bipolar add and suffer from anxiety and depression. .I was bad in school and no one bothered to help me so my thoughts went from anger to sadness and I tried to take my life at 13 I had no one to understand me..all I'm say is if you choose not to go along with meds try to make sure he always has someone to talk to. ..and never criticize his thoughts

My doctor and my daughters school both said they don't believe in diagnosing ADHD until 7.By that age, most kids should have outgrown all the extra energy and have learned listening and following directions.My daughter takes Adderall and she is so much calmer and can focus.As another poster said, try to eliminate food dyes.Im making way more of an effort and I have seen results in behavior.Also my daughter had an iron defiency and one of the side effects is bad behavior.Im happy to report since we are on vitamin routine, behavior improved.

My son didn't improve with Focalin much, but he got a lot of bad side effects, even to the point of chewing on himself. It's the end of the school year so we're not going to try anything different, but maybe in the fall.