Walk into any American high school and nearly one in five boys in the hallways will have a diagnosis of attention-deficit hyperactivity disorder. According to the Centers of Disease Control and Prevention, 11% of all American children ages 4 to 17—over six million—have ADHD, a 16% increase since 2007. When you consider that in Britain roughly 3% of children have been similarly diagnosed, the figure is even more startling. Now comes worse news: In the U.S., being told that you have ADHD—and thus receiving some variety of amphetamine to treat it—has become more likely.

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