Pop queen Carly Simon, whose hit "You're So Vain" was No. 1 on the charts in 1973, still struggles when she talks about the panic attacks that nearly crippled her successful singing career.
"I think it's the whole experience of being in front of people, exposing yourself and your talent is so unnatural," the still-striking singer said in an interview last week.
Simon was so paralyzed during a 1981 concert in Pittsburgh that audience members swarmed the stage to help her, rubbing the singer's arms and legs. She made it through that show, but during the second one, she collapsed in front of 10,000 fans.
Now, at 62, Simon has just released her first album of original songs in eight years, "This Kind of Love," and has launched a string of appearances that will test her ability to deal with the anxiety disorder that has haunted her for decades.
She began today with a live performance on ABC's "Good Morning America," followed by more performances on TV's "The Rachel Ray Show" and "The Ellen DeGeneres Show," leading up to the real test: a live concert in Miami on May 16.
Simon is not alone. The National Institutes of Health reports that 40 million Americans experience some form of anxiety disorder, causing their lives to be filled with fear and uncertainty. Of those, about 6 million have disabling panic attacks, twice as many of them women.
The singer says she has overcome "to a certain extent" the attacks that began in the early 1960s, using unorthodox techniques to keep her panic at bay.
At the height of her anxiety in 1996, during her very public breakup with singer James Taylor, she agreed to perform at then-President Clinton's 50th birthday party at Radio City Music Hall in New York City.
Before coming on stage, she asked the band's horn section to spank her, a technique she used to calm herself down.
"The whole orchestra was spanking me [on the bottom]," Simon explained. "The curtain went up and the trumpet player was off his perch and spanking me, and I don't think anyone knew it was happening. He stopped just in time."
Panic attacks are unlike the usual jitters that accompany speaking in public or a first date. Sufferers like Simon report a pounding heart, sweating and weakness. Some experience tingling hands, nausea or other smothering sensations. They usually produce a sense of unreality, a fear of impending doom or losing control.
Other high-profile stars have publicly confessed to experiencing panic attacks.
"American Idol's" Clay Aiken said his were triggered by the death of his stepfather and increased as he rose to fame. He later overcame his anxiety with the antidepressant Paxil.
The most famous of the stage-struck stars may be singer Barbra Streisand, who during a 1967 concert in New York's Central Park forgot the words to a song.
She was so traumatized by panic attacks, she was unable to sing publicly for 27 years. She made a comeback tour in 1994 after playing small venues and moving up to bigger venues.
Child actress Drew Barrymore, who overcame drug and alcohol addiction, admitted in 2006 that she was taking medications to deal with panic. Others like cooking show host Paula Deen, actress Kim Basinger and singer Donny Osmond have shared their stories of anxiety.
One of the most surprising victims of panic disorder may be Sigmund Freud, the father of modern psychiatry, who later dedicated his life to researching anxiety.