As an example, President JFK received regular injections containing high doses of amphetamines from his personal physician.
Then the risk of abuse and side-effects in the population were observed and it was banned.
Did JFK have ADHD? No, it just helped him with energy levels. Like it would anyone.
There are no conclusive bio-markers for ADHD. Therefore its not possible to say who doesn't have it and should not get stimulant medication.
The only commonality is that there is an impairment. It's not possible to say: this person has difficulty focusing and has ADHD but this person has difficulty focusing but doesn't have ADHD.
The board of psychiatrists who decide what symptoms constitute it just essentially make it up.
The only thing that is real and measurable is the level of impairment to someone's life.
Stimulant medications works, but it would work for anyone regardless of an ADHD cause. ADHD is like a catch-all for people who can't focus that doesn't match any other condition that could be resolved differently.
Stimulant medication definitely carries risks and health impacts. This is black and white.