I don't deny some children are harder to manage than others. I don't deny that Ritalin and related drugs make them easier to manage. I deny that they have a disease.
A reason to call the ocndition a disease is to make the negative effects of medication will be deemed acceptable. But the effects of long-term psychiatric medication during childhood are horrendous.
I have no objection to adults taking any drug they like to manage their own behavior.
single malt usually manages mine just fine ;)