Bipolar 1 and bipolar 2 are closely related conditions, but have crucial differences between them. According to the National Institute of Mental Health, around 2.6 % of the U.S. adult population has suffered from bipolar disorder in the past year, and about 3.9 % has it over the course of their life. If you’re concerned about a loved one with bipolar disorder or want to learn more about treatment options, finding out the differences between bipolar 1 and bipolar 2 is a crucial step. Bipolar Disorder Basics: Mania and Depression Bipolar disorder is characterized by periods of mania and periods of depression. While most people go through some periods where they feel a bit happier than usual or a bit sadder than usual, in bipolar disorder these differences are extreme and interfere with everyday life. Manic periods involve feeling very “up” or “high,” and being much more active and talkative than usual. People experiencing mania can get agitated and irritable, struggle to sleep, feel like their thoughts are racing, take risks, and feel like they can juggle a lot of tasks simultaneously. Conversely, during periods of depression the individual will often feel generally “down,” will sleep a lot more or less...