Some years ago, a friend told me that he had been diagnosed with a major depressive disorder and that his psychiatrist had given him a prescription for Forest Laboratories' popular SSRI antidepressant Celexa (chemical name, citalopram hydrobromide; $1.5 billion in sales in 2003). Knowing him to be a vociferous critic of the pharmaceutical companies, I asked whether he agreed that the origins of his unhappiness were biological in nature. He replied that he unequivocally did not. "But," he confided, "now I might be able to get my grades back up."

This guy was, at the time, a full-time undergraduate student who managed rent, groceries and tuition only by working two part-time jobs. He awoke before dawn each morning in order to transcribe interviews for a local graduate student, then embarked upon an hour-long commute to campus, attended classes until late afternoon, and then finally headed over to a nearby café to wash dishes until nine o'clock in the evening. By the time he arrived home each night, he was too exhausted to work on the sundry assignments, essays and lab reports that populated his course syllabi. As the school year dragged on, he had become increasingly disheartened about his slipping grades and mounting fatigue and decided, finally, that something had to be done. So he'd seen the psychiatrist and was now on Celexa.