Bipolar disorder has been described as a roller coaster, with manic highs and depressive lows.

"In a manic period, there's really no sleep involved -- like you stay up for a long time. It can be very productive. You can get things done for a while, then you start to lose your focus and you can't pay attention, and you just start to kind of come apart at the seams," says Zack Lamm, 22, an ITT Tech student who first experienced bipolar symptoms in high school.

"A depressed period is basically the opposite," he said. "There's just like a general apathy. You don't feel like doing anything. You don't want to hang out with your friends."

According to Dr. Ryan Moe, a psychiatrist and addictionologist at the Institute of Psychiatric Research at Indiana University, Lamm's experiences are typical for a person with bipolar disorder.

"This disorder has two components to it -- one is the elation and one is the depression. They kind of cycle back and forth," said Moe, who works with bipolar patients in clinics and hospitals.

More than 2 million Americans, or 1 percent of the population, suffer from bipolar disorder, according to the National Institute of Mental Health. Moe said the condition is not more likely among any one race or gender.

The disorder comes on suddenly, usually when people are in their early 20s. The first symptoms include acting differently for no apparent reason. For example, during a manic period, a person might start spending money recklessly or think God is speaking to him or her. In a depressive stage, bipolar patients might become suicidal or experience feelings of worthlessness.

The cycles can change unexpectedly or follow a pattern, and a lot of people feel and act normally in between extremes.

"It tends to be seasonal, and people can predict, 'I usually get manic in the spring. I'm depressed in the winter,' " said registered nurse Carrie Smiley, who coordinates the family genetics studies in bipolar disorder for Dr. John Nurnberger Jr., director of the Institute of Psychiatric Research.

Though the disorder is unique to every patient, there are a few differences between children and adults. Moe said early symptoms for children might include behavioral problems, irritability, and problems getting schoolwork done, traits also seen in attention deficit hyperactivity disorder patients. According to the Aug. 19, 2002, issue of Time magazine, up to 15 percent of children thought to have ADHD actually might have bipolar disorder.

Such was the case for 14-year-old Matt Bennett of Valatie, N.Y.:

"I had a lot of problems with school. I used to get in a lot of fights. That's why I got kicked out," said Matt, diagnosed with bipolar disorder a year and a half ago. "I used to punch holes in the walls all the time."

Bipolar disorder also might be misdiagnosed as major depression, schizophrenia and other mental disorders.

"Let's say somebody came to me in their adolescent years, 16 or so, and they're really depressed, and I diagnose a major depression. I don't know yet if they have bipolar disorder (until) they have a manic episode," Moe said.

There are two types of cyclers, rapid and nonrapid, according to Moe. "If you have four cycles in a year, then that means you would be considered a rapid cycler. And if you have less than that, then you are considered a nonrapid cycler, and approximately 85 percent of the people are nonrapid cyclers that have bipolar disorder."

Change in sleeping patterns, substance abuse and stress may trigger bipolar symptoms.

"Technically, substances are not the cause of a bipolar disorder, but they could cause you to have manic symptoms. Other triggers are stress. If you have lots of stress in your life, you can induce a mania, or you could induce depression, too, just with stress," Moe said.

To help control these cycles, patients are usually treated with medication, group therapy, individual counseling sessions with psychiatrists, or all three.

Matt undergoes all three forms of treatment and has tried various medications. "The medicine really doesn't help me, but I have to take it so I just do," he said.

Moe said medications play an essential part of the treatment of bipolar patients. Most patients are treated with lithium, Depakote (divalproex sodium) or Tegretol. However, severely depressed patients also may take an antidepressant.

Though Moe recommends medication, he recognizes the possible side effects. "What you have to remember is everybody's different, so everybody might have different side effects," he said. "There are some common ones that you might see with the lithium in children and adults . . . they might have tremors, maybe they get thirsty. Weight gain would be another one."

Matt has gained weight but has had no other side effect. Still, he remains skeptical of doctors. "They think they know everything about you," he said. "They try to get in my head, and I just don't let them."

Researchers are investigating gene therapy, although the illness defies a simple fix. "There's not going to be just a gene for bipolar disorder; it's gonna be multiple genes. . . . It expresses itself differently amongst families and individuals," Smiley said.

Moe said studies have shown that adopted children who have a biological parent with bipolar disorder have a higher incidence of developing the disorder themselves. The same is true of identical twins -- if one twin has the disorder, the chance that the other will be diagnosed is high.

With effective treatment, bipolar patients can lead normal lives.

"It has such a stigma, and yet bipolar disorder is similar to heart disease and diabetes in that it's very treatable. You can take medication and stay on medication and lead a perfectly normal life," Smiley said.

Despite his reluctance to take medication, Matt said that since his treatment, he has gained greater control of his life. "My life is good. I just accept myself for who I am."

REPORTERS: Peter DePaolo, 14; Allison Gardner, 13; Elizabeth Newkirk, 13.

NEXT WEEK: Zack Lamm discusses his experiences with bipolar disorder.