What kind of autism if I may ask?
If it's high functioning autism your child definitely does not need medication as long as there is a healthy environment i.e. being around lots of friends/people so that they can learn social cues growing up.
I've worked with a lot of autistic/adhd people and I was not even aware there were medications for autism? If I had to guess, do they perhaps prescribe anti anxiety/depression medicines?
If you manage to set an autistic child in the right path, they will excel the fuck out of life.
Regarding ADHD, make sure your kids' teachers sit your kids in the front of the classroom every single day, every single lesson. They need as much help and guidance as they can. Sometimes medication isn't enough. It has to be a lifestyle change for them. Sit right in front of them and watch them as they do HW, keep encouraging, motivating. One of the best therapies for ADHD as taught to me by specialists in the field is to make a schedule and stick to the schedule religiously. Structure is one of the most important things for somebody with ADHD. School 9 am, Home 4 pm, Dinner 5 pm, homework 6 pm, bath 8 pm, bed 9 pm etc. etc.
Best to do it now while they're young, so it becomes a habit for them into adulthood and throughout college, because when they become adults they for sure aren't going to do it.