Please let me know if this is not the right forum for my question. Tl/dr: I describe behavior and appearance and ask, "Does this ping for any drug(s) in particular?"

I work with kids and I think one of them is using drugs regularly. I am a mandated reporter and I have done those duties. In the course of doing that and trying to get this child help, I keep running up against people above me asking, "Well what do you think they're using, how would we figure that out?" I have ideas but they're based on nothing more than "This feels like interacting with [my family member] when he's high on [substance] so maybe look for [delivery method]?" This isn't enough because a) the people who can advocate for getting this kid help do not have that same experience as I did growing up, and b) I don't know all the possible matches for the symptoms I'm seeing. I know it's beyond the scope of my job, but I want to help this kid and so I would like to bring more concrete possibilities to my superiors.

My observations of the child: Mood swings between grumpy/mean/combative and spaced-out but vaguely content and almost overly polite...? Like, they will forget what they're doing and then kind of try to snap to and apologize but can't maintain any kind of engagement. It's like talking to someone who's concussed or fighting sleep. Their skin is off somehow, like really dull, with a grayish tinge and big dark undereye circles (nonspecific, I know.) They've noticably lost weight over the course of a few months. They seem to have trouble making their eyes focus, both in the sense of they don't really look at you normally when conversing and in the sense of they have intermittent trouble reading. If they are using, it seems to be something sneakable or long acting, because the child is with us for 6-8 hours at a stretch and I don't notice a clear pattern of under the influence/withdrawing at regular times. So, if this sounds like anything specific and you don't mind sharing what and why, I would sure appreciate it.

Eta: I have tried to find info online but apparently my search game sucks bc all I get is vague "Drugs--all drugs! in general!--make you super ugly and bad at everything" type material from rehab websites and "10 signs your teen is doing (nonspecific) drugs.gov."