Like major depression, bipolar disorder is characterized by sadness, fatigue, a loss of enjoyment in everyday activities and disruptions in appetite and sleep patterns. But individuals with bipolar disorder differ from patients with major depressive disorder in that they experience what’s called mania or hypomania – emotional highs, bursts of extreme energy and severe irritability that ranges in intensity and duration.

– Kirstin Fawcett

via Bipolar Disorder: What You Need to Know.