Need advice on addiction treatment!

Hi all,
This is my first post here. Recently I came to know that my son is using some sort of drugs. When I asked him about this, he told me that those drugs are the medication for insomnia. I researched about the drug (Halcion) and came to know that those medicines are highly addictive and dangerous in nature. Literally, I was shocked and confronted him for lying to me. He throws a fit over me. I never saw this side of my son. It's been a week since we talked to each other. He made efforts to reconcile but I'm the one who is resisting. I told him, if he wants to reconcile then he should stop taking those drugs and he promised me that he won't use it again. But I'm not yet convinced. I'm worried about his health and decided to take him to a wellness treatment centre in Toronto for drug addiction treatment and counseling. I haven't discussed this with him. I hope he will be okay with my decision. He is only 20 years old. Will this treatment have any negative impact on his health in the future?