Subtle signs might include a change in style of clothing, makeup or the amount of jewelry a person wears.
These indications were precisely what Steve demonstrated before he lost his first job as a teaching fellow in psychology at the State University of New York at Stony Brook.
"I sort of reinvented myself," said Steve, who said he wore a "uniform" of jeans, flannel shirts and sneakers. "Then I had this complete and total desire to wear Hawaiian shirts, bell bottoms and platforms."
His students started noticing other signs of mania; he jumped from point to point in a lecture and got angry when others couldn't follow.
"Mania is by no means a euphoric state," said Steve. "Try disagreeing with me when I'm manic, and I'm evil; I become quite combative."
Later, when Steve ended up hospitalized with depression, he was surprised to find his co-workers -- specialists in the field of psychology -- shunned him.
"They had fixed boundaries between where they sat and where I was," said Steve. "They saw me, and they thought, 'If it can happen to him, it can happen to me, it can happen to anybody.'"
Steve eventually decided that he didn't have the stability to get through the Ph.D. program.
"There's still quite a bit of stigma in the public," said Sue Bergeson, CEO of the Depression and Bipolar Support Alliance. She herself has bipolar disorder.
In a 2004 poll, the DBSP found one out of five people believed that people with bipolar disorder were incapable of holding down jobs or keeping up personal relationships. One in six said they shouldn't have children, said Bergeson.
However, if treated, people with bipolar disorder may be quite functional. With long-term support, medication, therapy and a stable job, they may not have an episode for years, or even decades, said Sachs.
The challenge is to find and stick to treatment, which, said Bergeson, is made much more difficult by the stigma associated with the disorder.
Bergeson, now 50, kept up a successful career in nonprofit groups for years while keeping her disorder a secret. She paid out-of-pocket for treatment and medications, fearing that someone at work would find out about her condition through her insurance.
"I never told anyone," she said. "I just told my family, not even my friends. It was something I didn't want to talk about. I was ashamed."
That all changed when her sister, who also had bipolar disorder, committed suicide in 1999.
"I thought, 'Her life was very, very painful, and I need people to understand about these illnesses, and I need to rethink how private I've been," said Bergeson.
Ironically, Bergeson said, research shows the best way to reduce the stigma of mental illness is for people to learn that they know someone who has one.
"Another reason to talk about this in the workplace is to make sure mental health insurance is on par," said Bergeson, who said that her sister's insurance only covered 10 days in a hospital and 20 visits to a therapist for mental health -- not for a year, but 20 visits for her entire life.
"We lost our dear sister, and we are not staying quiet -- no way," said Bergeson.