"I used to think I was a drug addict, pure and simple -- just someone who could not stop taking drugs willfully," said Fisher in a December 2000 interview with Diane Sawyer on ABC News. "And I was that. But it turns out that I am severely manic depressive."
However, after years of struggle and a breakdown that kept her in a hospital for two weeks, Fisher has come to terms with her condition.
"I outlasted my problems," Fisher said. "I am mentally ill. I can say that. I am not ashamed of that. I survived that, I'm still surviving it, but bring it on. Better me than you."
While the English actor and comedian imbued drollery into British TV favorites such as "Jeeves and Wooster" and "Black Adder," he's had to do it while dealing with bipolar disorder.
"I [suffer], according to a psychiatrist at least, from cyclothymia, which is sometimes called 'bipolar light,'" Fry said in a 2006 seminar at St. Andrew's University.
While Fry explained that his condition generally has less severe symptoms, he reached a dangerous low point in 1995, when he walked out of a play he was starring in and came very close to killing himself.
"I went into my garage, sealed the door with a duvet I'd brought and got into my car," the comedian said in a BBC documentary "Stephen Fry: The Secret Life of the Manic Depressive."
"I sat there for at least, I think, two hours in the car, my hands on the ignition key," he said.
After that, Fry was diagnosed with the bipolar disorder.
"I'd never heard the word before," Fry said in the documentary. "But for the first time, at the age of 37, I had a diagnosis that explains the massive highs and miserable lows I've lived with all my life."
Now, Fry uses his celebrity to create awareness about bipolar disorder.
"I'm in a rare and privileged position of being able to help address the whole business of stigma," Fry said in his documentary, "and why it is that the rest of society finds it so easy to wrinkle their noses... when confronted with an illness of the mind and of the mood -- especially when we reach out with such sympathy towards diseases of the liver or other organs that don't affect who we are and how we feel in quite such devastating complexity."
Though he played the part of Rocky's iconic boxing trainer, Mickey, in "Rocky," Burgess Meredith might have needed some coaching of his own when dealing with his bipolar disorder.
Although younger generations may not recognize Meredith -- he died in 1997 -- he was well-known in his era, playing the Penguin in the 1966 "Batman" TV series and starring in the 1939 version of "Of Mice and Men."
He was also known in Hollywood for his violent mood swings and temperamental behavior. Rumored as woman-chaser, the actor married four times.
Meredith explained his changeable behavior in his autobiography, "So Far, So Good," writing that he was diagnosed with cyclothymia, a milder form of bipolar disorder.
Like many people who suffer from bipolar disorder, Meredith had a difficult childhood.
"All my life, to this day, the memory of my childhood remains grim and incoherent," Meredith wrote in his autobiography. "If I close my eyes and think back, I see little except violence and fear."
Apparently, abuse or neglect during early years can act as a trigger for the disorder.