I guess it's only fair that I reveal my bias here: I am deeply skeptical of people who claim to have a philosophical or political "answer" to "mental illness". In my experience, most such people seem to be utterly unfamiliar with the effects of unusual physiological states on the mind, and ultimately find their inspirations in the more flowery and idealistic schools of philosophy rather than in the scientific crucible of rationality and empiricism (neither is sufficient on its own: the two must be joined to make any sense of the world; this is, at any rate, my reading of Kant and his critics).
All that said, I'm a little confused by your invocation of "R.D. Laing etc". Usually, the name I see paired with R.D. Laing is Thomas Szasz, and I am far more receptive to the former than the latter. As far as I understand it, they had some pretty deep disagreements. Perhaps Foucault is closer to Laing than to Szasz, and you meant something closer to Foucault's formulation of mental illness, but I am less familiar with his ideas. I admit a certain reluctance to risk exposing myself to yet another flavor of pontification uninformed by experience (there are so many to choose from, and it seems that they uniformly exhaust my patience; I can only spare so much effort entertaining "learned" people who dismiss my lived experience as utter delusion).
As it happens, I was prescribed an ADHD drug by the same psychiatrist who ultimately urged me to pursue the physiological diagnosis whose treatment I actually found helpful. I found that the drug was only modestly helpful at best, and he was quite receptive to my assessment that I should discontinue it. I actually still have almost a month's supply in my cupboard, have felt no temptation to (ab)use it, and am not sure whether I should turn it in to the DEA (it being Schedule II, which is supposedly accounted with some precision) or quietly dispose of it in the bags of my paper shredder.