Episodic mood disorder primarily characterized by depressed mood and anhedonia that lasts for at least 2 weeks.

Epidemiology:- Sex: ♀ > ♂- Lifetime prevalence: 15-25%- The peak age of onset is in the 20s.

Diagnostics: ≥ 5 symptoms, for at least 2 weeks- Depressed mood present most of the day, almost every day- Sleep disturbance (insomnia or hypersomnia)- Loss of interest or anhedonia- Feelings of worthlessness or guilt- Fatigue or loss of energy- Diminished concentration, ability to think, or make decisions - Weight change due to appetite change- Psychomotor changes- Suicidal ideation- Clinically significant distress or impaired functioning in important areas of life (e.g., work, school)- No history of a manic or hypomanic episode

- Suicide screening and assessment: indicated for all patients- Polysomnography: indicated in sleep-onset insomnia (the patient is unable to fall asleep) and sleep-maintenance insomnia (the patient falls asleep but wakes up often)- Thyroid function tests: to rule out hypothyroidism

Treatment:- Single episode: Continue medication for ≥ 6 months- Multiple episodes: Continue medication for ≥ 2 years- If the patient is in remission: Continue antidepressants for at least 4-9 months- First-line: SSRIs- SNRIs- Bupropion: lowers seizure threshold, less sexual dysfunction compared to SSRIs, and can also treat tobacco dependence- Mirtazapine: significant weight gain- Suicidal patients: Lithium should be combined with an antidepressant as prophylaxis to prevent recurrence.- Psychotherapy: Cognitive-behavioral therapy; Interpersonal therapy; Psychodynamic psychotherapy; Family and couples therapy