IIRC, methylphenidates (Ritalin, Concerta) will not show up as amphetamines while Adderall (amphetamine salts) will. If he brought the labeled bottle with him I doubt it would be a problem.
Son recently applied for jobs as a scuba instructor and some of the shops required drug testing. I guess they frown on putting the lives of their clients in the hands of stoned people. Whoda thunk? 
I’m interning in the administration side of a major hospital affiliated with a public university. I was drug tested for the usual five (THC, opiates, PCP, cocaine, amphetamines) as well as nicotine.
I was drug tested 30 years ago when I started my first job at the NYSE, and did at my second job and third one, my current one screens as well. Among other things, they are afraid of liability in the securities industry and almost everyone does it. A lot of it is cya, if anything goes wrong and it turns out someone is using drugs, there can be liability around it, risk.
If you are taking a drug test, it is always wise to let them know the kind of things you routinely take, whether it is prescription meds, cold medications, or herbal supplements, unless they have changed things the tests they run are chromotography tests, which are not that accurate (and yes, eating a poppy seed cake can give a false positive for opiates). If in doubt, tell them, they will know what to look for, and may schedule a more accurate test if they know you took pseudephodrine (spelling is probably crap). A friend at my first job was epileptic and took barbiturates to prevent seizures, he had a bizarre sense of humor and didn’t tell them, he was lucky that they actually checked with him, and he then gave them his doctor’s name and his prescription.these days for doing that he likely wouldn’t be hired.