Neuropsychologist Ian Robertson writes at Psychology Today:
Attention Deficit Hyperactivity Disorder is being grossly overdiagnosed for a range of commercial and social reasons. For millions of children to be taking powerful drugs which can have dangerous side effects is an example of the sort of pharmaceutical scandal that emerges every few decades, usually as a result of lazy and lax prescribing habits by doctors.
Dr. Robertson cites the 20th century over-use of amphetamines and benzodiazepines.
h/t Dennis Mangan