Same principle as the weed doctor. You just need a therapist willing to sign off on whatever you tell them. Quite honestly it’s probably even easier than that, normal intake for drug abuse is a questionnaire about usage history.

So what all young men should be doing now is going to get drug abuse treatment just to get the intake paperwork done. Tell them you’ve been using since you were 13 and can’t stop. Give them a phone number one digit off from yours if you don’t want a phone call to remind you to come to treatment since you’re just trying to establish a history.