How can I find a better Psychiatrist to prescribe medication for my Autistic Son?

The Doctor we see simply prescribes the medication. He is like a drug pusher. He wants all his patients to be involved in his studies . Drug companies pay him well. My Son will never be involved in any studies.
This Doctor has no compassion or comprehension of my Son’s needs.The medication helps my Son to be more mellow. I do worry about side effects.
My Son is Autistic he is a Human being not a rodent.