Summary Table of Mood Episodes

Episode	Description	Minimum Duration	Main Features	Distinctive Notes
Major Depressive Episode	Phase marked by deeply depressed mood and significant functional impairment.	At least 2 consecutive weeks	Depressed mood, anhedonia, sleep and appetite changes, fatigue, guilt, suicidal ideation.	May occur in major depressive disorder or bipolar disorders.
Manic Episode	Pathological expansion of mood with increased energy, ideation, and reactivity.	At least 1 week (or shorter if hospitalization is required)	Euphoria, pressured speech, decreased need for sleep, grandiosity, impulsivity, risky behavior.	Key feature of bipolar I disorder; often requires urgent intervention.
Hypomanic Episode	Milder form of mania with similar but less severe and impairing symptoms.	At least 4 consecutive days	Elevated or irritable mood, increased activity, talkativeness, heightened energy without marked impairment.	Characteristic of bipolar II disorder; often initially unrecognized.
Mixed Episode	Simultaneous or rapidly alternating depressive and manic/hypomanic symptoms.	Variable (DSM-5: at least 3 symptoms from the opposite pole)	Irritability, agitation, unstable mood, fatigue with motor energy, suicidal ideation + impulsivity.	High suicide risk; challenging to treat; common in young adults.

References

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