How Do I Get My Son Off Drugs?

My step-son is 25. Four years ago, he was caught with Marijuana at our home and said he had only tried it once. My son also has Type 1 Diabetes. Two weeks ago, he went to the hospital and was throwing up. When we asked him about it, he said he had not been checking his blood sugar regularly. When asking around to his friends, we found out he had been taking Cocaine. When confronting him about it, he said he stopped about 6 months ago. He is a big kid (6’2″ and normally 170 pounds). We have not seen him since May and he always says he is too busy to come to our home. He sleeps a lot and is depressed. I don’t know what I can do. He lives with his mom and my husband and I have spoken with her. She agreed to give him drug tests every once in a while, but I just do not think she will. I think he is scared to come to our home in fear he will get one. Even if he did come up, the drugs only stay in your system 1-2 days. What should I do?

Should I say something or will that ruin my son’s chances of being popular??

He has been assigned a pd, I can help him pay for a lawyer but he dose not want 1. Will I just be wasting money on a lawyer?

Should i say something, I don’t wanna hurt his chances of being popular. I want him to be able to go to all the underage drinking parties.

I don/t see him often, but the last few times his nose is runny, eyes are watery, and spends quite a bit of time outside or in the bathroom.

I found a white powder in my son’s room, and I’m curious as to what symptoms I should be looking for if and when my son is snorting/injecting the devil’s dandruff.