Yes, it is possible for someone to be clinically depressed without experiencing episodes of mania or hypomania associated with bipolar disorder II. Bipolar disorder II is characterized by recurrent depressive episodes, but the key distinguishing feature from unipolar depression (major depressive disorder) is the presence of hypomanic episodes.
Hypomania is a milder form of mania and is marked by a distinct period of elevated or irritable mood, increased energy, and other symptoms that are less severe than those seen in full-blown mania. In bipolar II disorder, individuals will experience episodes of major depression and hypomania, but not full mania.
On the other hand, unipolar depression, or major depressive disorder (MDD), is characterized by recurrent episodes of major depression without any history of mania or hypomania. People with MDD experience prolonged periods of low mood, loss of interest or pleasure in activities, changes in sleep and appetite, fatigue, feelings of worthlessness or guilt, and sometimes suicidal thoughts.
It's essential for a mental health professional to accurately diagnose a person's condition to determine the appropriate treatment approach. The presence or absence of hypomania or mania is one of the factors considered in distinguishing between bipolar II disorder and unipolar depression. Proper diagnosis is crucial, as the treatment strategies for bipolar II disorder and unipolar depression can be different.