We don't know everything Josh has taken before or after turning 18, when Clint cut him free as an adult and Josh stopped taking his prescription meds, but he did say he was prescribed Ritalin and Strattera. Strattera is a non-stimulant alternative to Ritalin, Adderall, etc. He dropped all ADHD medication when turning 18 and says he hated them. He has never said he was prescribed Adderall ever before. Like all drugs that are popularly recreational, Josh is known to lie to appear cool, a bad boy, rockstar, etc.
A bit TMI but I think it's informative:
I don't believe Cool Taste's Adderall accusation. I am prescribed Adderall and it's become increasingly harder to get because of tighter DEA restrictions and there's an ongoing shortage since last year. On top of that, the black/grey markets for amphetamine or similar "research chemicals" is slim and expensive in the US. Speed is much more popular in EU as far as illicit use and availability, as Rotterdam is the largest shipping port where it arrives from China--much of it stays in the EU market. Adderall/amphetamine street price is high and has gone up even more since the shortage. To be prescribed Adderall these days in the US, you have to see a doctor once every three months, the doctor has to send a script for each month through the DEA and to the pharmacy to have it on record. If the pharmacy is out, you just can't transfer it, you have to ask the doctor to cancel the scripts they electronically sent, then re-write them to a new pharmacy. Since COVID, telehealth for it has been allowed in many states, but since Biden announced COVID is over, the time for getting a Schedule II controlled substance via telehealth is expiring soon without sign of any renewal. In many states, they now even do piss tests every three months to approve it. If you're positive for any common piss test drug, you can be denied it and then that's on your record and risk being blacklisted from ever getting it again. The states that have these rules aren't strictly blue or red, so Wyoming could easily have implemented it. All this said, the days of 5-15 years ago when Adderall availability flowed through college campuses is a lot more prohibitive.
I doubt Josh has been seeing a doctor in any form, has any connections that have it (especially in a place where the street market's biggest drug outside of weed is meth), and/or paying $10-$20 per 10mg pill.
I've always been of the opinion that Josh isn't on pills or whatever as much as anyone likes to speculate after certain videos. Stuff like the cooking videos, he is parroting other food channels he watches and tries to appear more upbeat and like Daym Drops, etc. He always says shit like "Yo Cuz, this food hack is slappin', B., you don't even know!" only in food videos.
That said, if Josh is getting pills, it's some form of muscle relaxers and not as regular as people want. He has mentioned that for a while and it wouldn't be surprising if Walt has them if he is getting pills from them. I've always thought tramadol given my personal experience seeing a lot of old Vietnam vets getting it through the VA fairly easily after the opioid crisis made it very hard to get oxycodone, etc. I think he goes over to the Knight residence because he is invited, feels wanted, and is lonely. He has no friends anymore and nothing to do. The Knights get some booze, weed, cigarettes, and company too in exchange. He also gets the chance of potentially seeing Ellen if she's there. She doesn't live there anymore per public records, but isn't far away. I figure her old room is there and visits regularly.
Finally, all this said. Josh obviously has an elementary understanding of illicit, recreational drugs. He said he has taken "nearly all the drugs" which is obviously a lie to support his rockstar image and part of that is broadly lumping "pills" as a drug. He thinks all the drugs is like nine or ten. Josh's drug education is mostly D.A.R.E. level and will loathe meds forced to him when he was prescribed them but will gravitate towards them if it supports his image. If Clint or any authority would approve of it, he will not like it. People have said he has Oppositional defiant disorder (ODD), which I don't think he's ever mentioned, but it's not surprising. He wants to be a bad boy rebel and mentally a 13 year old in many ways, as Clint claimed regardless of whether or not you approve of his parenting.