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Erratic behavior

When they are in a manic phase, people with bipolar disorder can have an inflated self-esteem.

"They feel grandiose and don't consider consequences; everything sounds good to them," Dr. Malone says.

Two of the most common types of behavior that can result from this are spending sprees and unusual sexual behavior. "I have had a number of patients who have had affairs who never would have done that if they weren't in a manic episode…during this episode they exhibited behavior that is not consistent with what they would do normally," he says.

Next: Sleep problems