What distinguishes bipolar disorder from other mood disorders?

Bipolar disorder is characterized by the presence of both manic and depressive episodes, which is a defining feature that distinguishes it from other mood disorders. In bipolar disorder, individuals experience extreme mood swings that include highs (mania or hypomania) and lows (depression). This cyclical nature of moods is pivotal to the diagnosis, as it sets bipolar disorder apart from unipolar disorders, which typically involve only depressive episodes without the manic phases.

The presence of these alternating states not only affects an individual's emotional state but also impacts their behavior, thought processes, and overall functioning. This duality of symptoms – experiencing both the euphoria or irritability during manic episodes and the deep sadness or lack of interest during depressive episodes – is what fundamentally defines bipolar disorder and differentiates it from other mood disorders that may be characterized by a single mood state.