"Anxiety is something I have always had, especially during times of change," said Craig, 40, who lives in Scotland, Ontario. "But I was never worried about the level of anxiety, and it never prevented me from leaving the house, driving, socializing or even speaking in front of people."

Her doctor referred her to an anxiety clinic, where a nurse asked Craig dozens of yes-or-no questions - are you afraid of snakes? do you hear voices? do you vomit from anxiety? - and made a diagnosis. "She said, 'Let's call it Generalized Anxiety Disorder with a touch of social phobia,'" Craig said.

That didn't feel right to her, but the clinic's psychiatrist agreed with the nurse and said Craig's concerns about motherhood constituted an anxiety disorder, a form of mental illness, and prescribed Pfizer's Effexor and then GlaxoSmithKline's Paxil. Craig says the drugs exacerbated the very anxiety that she doubted required medication.

Craig's case is one of millions that constitute an extraordinary trend in mental illness: an increase in the prevalence of reported anxiety disorders of more than 1,200 percent since 1980.

In that year, 2 percent to 4 percent of Americans suffered from an anxiety disorder, according to the American Psychiatric Association's Diagnostic and Statistical Manual (DSM) of Mental Disorders, used by psychiatrists and others worldwide to diagnose mental illness.

In 1994, a study asking a random sample of thousands of Americans about their mental health reported that 15 percent had ever suffered from anxiety disorders. A 2009 study of people interviewed about their anxiety repeatedly for years raised that estimate to 49.5 percent - which would be 117 million U.S. adults.

Some psychiatrists say the increase in the prevalence of anxiety from about 4 percent to 50 percent is the result of psychiatrists and others "getting better at diagnosing anxiety," as Dr. Carolyn Robinowitz, a past president of the APA who is in private practice in Washington, D.C., put it. "People who criticize that are showing their bias," she said. "When we get better at diagnosing hypertension, we don't say that's terrible."

Critics, including other leading psychiatrists, disagree. They say the apparent explosion in anxiety shows there is something seriously and dangerously wrong with the DSM. Its next edition, due in May, would lower the threshold for identifying anxiety.

The criticism rests on three arguments. First, the DSM fails to recognize that anxiety is normal and even beneficial in many situations, so it conflates a properly functioning brain system with a pathology. Second, the DSM's description of anxiety is more about enforcing social norms than medicine.

Finally, they say, anxiety is adaptive. Its brain circuitry was honed by evolution for a purpose. Only when that mechanism misfires should a person be diagnosed as mentally ill.

"No human emotion is more basic than anxiety," said sociologist Allan Horwitz of Rutgers University. "Many forms of it simply should not be categorized as disorders, because they're the result of the way people evolved thousands of years ago, rather than something going wrong."

IDENTIFYING THE TRULY ILL

Horwitz and other critics recognize that when the brain's anxiety system misfires it can prevent people from functioning, as when someone is unable to leave home, interact with friends and family or walk past even a leashed dog. But the anxiety system is working properly when it makes someone afraid of heights or wild dogs or threatening strangers.

"Anxiety or panic symptoms that have been severe, persistent and cause clinically significant distress or impairment need to be diagnosed promptly," said Dr. Allen Frances, a psychiatrist who led the previous DSM revision and questions some of the new criteria. "Very effective treatments are available."

"We don't oppose people getting treatment," said Horwitz, co-author of the new book "All We Have to Fear: Psychiatry's Transformation of Natural Anxieties into Mental Disorders." "But people are much too willing to think they have a disorder that requires treatment."

Many psychiatrists don't see it that way. Under changes for the DSM-5 proposed by experts convened by the APA, symptoms such as excessive worry, restlessness, feeling on edge, avoiding activities that cause anxiety, and being overly concerned about health or finances or family would have to be present for only three months rather than six to justify a diagnosis of Generalized Anxiety Disorder (GAD). And people would have to display one physical symptom, not the current three.

"Because its threshold for GAD is set so ridiculously low, DSM-5 will mislabel as mentally ill many people who are experiencing no more than the normal and expected worries of everyday life," said Frances.

Dr. Donna Rockwell, a clinical psychologist who has organized opposition to aspects of the DSM-5 process, warned that "unless come to their senses, GAD will be identical to the existential worries all of us face as part of being human." That will bring "a bonanza to the drug companies," she added, opening the floodgates to "more inappropriate, expensive and potentially harmful drug use."

Drugmakers reported $661 million in U.S. sales of anti-anxiety drugs last year, according to IMS Health. Most psychiatrists see that as evidence people suffering from mental illness are getting help. On Thursday the Pharmaceutical Research and Manufacturers of America issued a report touting the many drugs being developed for mental illnesses, including 26 for anxiety.

"When anxiety symptoms impair a person's functioning, what's so bad about helping them get back to a normal state and using medication if appropriate?" asked Robinowitz.

The message that what used to be considered part of the human condition is pathological is getting through, at least to some people.

James Heaney, 44, told his family physician in 2000 that he often felt shy or mildly depressed in social situations - "like I saw on the TV commercial" telling viewers to "ask your doctor" about social anxiety. "There was no in-depth evaluation of my symptoms," said Heaney, then a network administrator for a school district near Rochester, New York. After a 10-minute interview, he had a diagnosis of "mild social anxiety" and a prescription for Paxil. "For such a powerful drug," he said, "it was remarkably easy to get."

EVOLUTIONARY RESPONSE

Research over the past decade shows that feeling anxious is how the brain's emotion centers send signals to its thinking centers that something is amiss.

For instance, it is normal to be anxious over a sick child, a loved one's illness, unemployment or other setbacks in life, said New York University sociologist Jerome Wakefield, co-author of "All We Have to Fear."

"The feeling of anxiety tells you something poses a threat, which can motivate you to stay vigilant" - about, say, a change in a sick child's symptoms, he said.

In the Paleolithic era, when our prehistoric ancestors lived in small clans, how people were viewed by strangers and kin could determine survival. So when people fret over going to a party, giving a speech or otherwise subject themselves to judgment, it reflects an adaptive response to the millennia-old need to be attuned to other people's disapproval, researchers say. Anxiety about public speaking accounts for about half the diagnoses of social anxiety disorder.

"There is great evolutionary and survival value in anxiety, which makes it difficult to identify as an illness or pathology," said psychologist Frank Farley of Temple University.

Anxiety was working properly among survivors of Hurricane Katrina, Wakefield and Horwitz contend. Years after the devastating 2005 storm, schools, housing, policing and other aspects of life in New Orleans had still not returned to normal. Using DSM criteria, a 2007 study concluded that half the surviving residents were "mentally ill" because they experienced anxiety about those lingering effects.

"If you survived Katrina, anxiety is not a sign of mental illness; it's the brain working as it should," said Wakefield. Such emotions can spur survivors to agitate for rebuilding neighborhoods, he said.

Another concern is that by labeling normal human variation - being more anxious, fearful or worried than the average person - a mental illness, psychiatry is venturing into social control.

"To suggest that anyone who's afraid to speak in front of hundreds of strangers has a mental illness creates social pressure to change," said Wakefield. "And that pushes psychiatry away from medicine and into enforcing social values."

BAD REACTIONS

In retrospect, Marla Royce (who asked that her real name not be used) thinks her brain's anxiety system was working as evolution intended. A successful Texas novelist, she was upset about the death of her father in 2004. Her anxiety was compounded when her publisher did not promote her new book, leading Royce to worry that her writing career was over.

"It was just garden-variety situational anxiety," she says now about the agitation and disorientation she felt.

Royce said she went along "trustingly and blithely" when a family physician diagnosed her with GAD. "He said the pharma sales rep had just left some samples, so he gave me Lexapro," to which a psychiatrist added Paxil, Xanax and Klonopin.

She became dependent on the drugs, taking ever-higher doses. Her psychiatrist told her that "was proof my anxiety disorder was out of control and that I would have to be medicated for life." She suffered "steadily declining mental and physical health" until she stopped the meds five years ago and shared her story with the online support group PaxilProgress.

James Heaney's shyness turned to numbness on Paxil. "It made me insular and nonresponsive to my friends and family," he said. "My mood became very variable," and co-workers told him they felt uncomfortable asking him for computer help as they once did "because they weren't sure which James they would get."

He weaned himself off psychiatric drugs in 2011. The social anxiety he still occasionally feels "is a relatively easy problem to deal with," he said.

For Cynthia Craig, the drugs she was prescribed triggered "excruciating anxiety symptoms like I had never experienced in my entire life."

"I told my doctor I don't want to be on anything," she said. "My anxiety is predictable and something I can handle."

(Reporting by Sharon Begley; Editing by Michele Gershberg and Douglas Royalty)

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