ADHD drugs almost certainly means adderall which is pretty heavily abused as a recreational drug, especially on college campuses. It's relatively easy to acquire a prescription and it's an amphetamine.
Edit: good article about the subject in general https://www.nytimes.com/2016/10/16/magazine/generation-adder...
> In college, especially, these drugs are used as study-aid medication to help students stay up all night and cram.
> My friend pulled two blue pills out of tinfoil and handed them to me. An hour later, I was in the basement of the library, hunkered down in the Absolute Quiet Room, in a state of peerless ecstasy.