-->When patients have trouble with panic attacks and come to psychologist Norman B. Schmidt, PhD, he asks if they drink coffee and whether the anxiety strikes shortly afterward, say, in the morning on the way to work.

If their answer is "yes," he has a surprising treatment: More coffee. But now these patients carefully sip their java while noting their physical reactions. That way, Schmidt hopes, they'll learn to recognize their pounding hearts and quickened pulses for what those symptoms really represent: a caffeine-induced buzz.

With coffeehouses springing up on every street corner, researchers like Schmidt are increasingly concerned about caffeine's role in panic and other anxiety disorders. Indeed, caffeine's power has become so well recognized that the American Psychiatric Association has added three related disorders to its list of official diagnoses: caffeine intoxication, caffeine-related anxiety, and caffeine-related sleep disorders.

"Caffeine is the most widely used mood-altering drug in the world," says Roland Griffiths, PhD, a professor in the departments of psychiatry and neuroscience at the Johns Hopkins University School of Medicine. "People often see coffee, tea, and soft drinks simply as beverages rather than vehicles for a psychoactive drug. But caffeine can exacerbate anxiety and panic disorders."

It's no surprise that caffeine gets so much attention from scientists these days. After all, 80% of Americans drink it. In fact, occasional coffee consumption rose 6% in the last year alone, according to the National Coffee Association. At the same time, panic and other anxiety disorders have become the most common mental illnesses in the United States. When caffeine overlaps with these disorders, the result can be trouble.

"If you tend to be a high-strung, anxious person," says Schmidt, "using a lot of caffeine can be risky."