What is characterized by fluctuating feelings of extreme happiness and severe depression?

Bipolar disorder is defined by fluctuations in mood that involve periods of extreme happiness—often referred to as mania or hypomania—and severe depression. Individuals with this condition may experience episodes of elevated mood where they feel excessively energetic, euphoric, or irritable, which can alternate with episodes of deep depression where they may struggle with feelings of hopelessness, fatigue, and a lack of interest in activities. These mood swings can significantly impact one’s daily functioning and relationships.

Seasonal affective disorder relates more to depressive episodes that occur at specific times of the year, typically influenced by changes in sunlight exposure. Panic disorder involves recurrent panic attacks and intense fear that may cause significant distress but does not include the prolonged mood swings characteristic of bipolar disorder. Obsessive-compulsive disorder is primarily focused on unwanted, intrusive thoughts and repetitive behaviors or compulsions and does not encompass the mood fluctuations seen in bipolar disorder.