In 1987, prior to Prozac hitting the market and the current ubiquitous use of antidepressants and other psychiatric drugs, the U.S. mental illness disability rate was 1 in every 184 Americans, but by 2007 the mental illness disability rate had more than doubled to 1 in every 76 Americans. Robert Whitaker was curious as to what was causing this dramatic increase in mental illness disability. The answers are in his new book, Anatomy of an Epidemic: Magic Bullets, Psychiatric Drugs, and the Astonishing Rise of Mental Illness in America (Crown Publishers, April 2010).

Whitaker’s findings will create a problem for both Big Pharma and establishment psychiatry, but his credentials and his craftsmanship will make it difficult to marginalize him.

Whitaker is the author of four books including Mad in America, about the mistreatment of the mentally ill; and as a reporter for the Boston Globe, he won a George Polk Award for medical writing, a National Association of Science Writers Award for best magazine article, and was a finalist for a Pulitzer Prize. In the tradition of Michael Pollan, Eric Schlosser, and other investigative reporters who get taken seriously, Whitaker is scrupulous, fair, and describes complex phenomena in a way that is easy to understand.

Levine: So mental illness disability rates have doubled since 1987 and increased six-fold since 1955. And at the same time, psychiatric drug use greatly increased in the 1950s and 1960s, then skyrocketed after 1988 when Prozac hit the market, so now antidepressant and antipsychotic drugs alone gross more than $25 billion annually in the U.S. But as you know, correlation isn’t causation. What makes you feel that the increase in psychiatric drug use is a big part of the reason for the increase in mental illness?

Whitaker: The rise in the disability rate due to mental illness is simply the starting point for the book. The disability numbers don’t prove anything, but, given that this astonishing increase has occurred in lockstep with our society’s increased use of psychiatric medications, the numbers do raise an obvious question. Could our drug-based paradigm of care, for some unforeseen reason, be fueling the increase in disability rates? And in order to investigate that question, you need to look at two things. First, do psychiatric medications alter the long-term course of mental disorders for the better, or for the worse? Do they increase the likelihood that a person will be able to function well over the long-term, or do they increase the likelihood that a person will end up on disability? Second, is it possible that a person with a mild disorder may have a bad reaction to an initial drug, and that puts the person onto a path that can lead to long-term disability. For instance, a person with a mild bout of depression may have a manic reaction to an antidepressant, and then is diagnosed with bipolar disorder and put on a cocktail of medications. Does that happen with any frequency? Could that be an iatrogenic [physician-caused illness] pathway that is helping to fuel the increase in the disability rates?

So that’s the starting point for the book. What I then did was look at what the scientific literature — a literature that now extends over 50 years — has to say about those questions. And the literature is remarkably consistent in the story it tells. Although psychiatric medications may be effective over the short term, they increase the likelihood that a person will become chronically ill over the long term. I was startled to see this picture emerge over and over again as I traced the long-term outcomes literature for schizophrenia, anxiety, depression, and bipolar illness. In addition, the scientific literature shows that many patients treated for a milder problem will worsen in response to a drug– say have a manic episode after taking an antidepressant — and that can lead to a new and more severe diagnosis like bipolar disorder. That is a well-documented iatrogenic pathway that is helping to fuel the increase in the disability numbers.

Now there may be various cultural factors contributing to the increase in the number of disabled mentally ill in our society. But the outcomes literature — and this really is a tragic story — clearly shows that our drug-based paradigm of care is a primary cause.