Depression is a mental disorder that is characterized by dysphoric or depressive mood for a duration of minimum 2 weeks, along with associated symptoms of:
1. Anhedonia: Loss of pleasure in otherwise pleasurable situation.
2. Appetite variation: Either increased or decreased appetite due to effect in circadian rhythm.
3. Sleep disturbances might include:
a) Insomnia: Early morning awakening/irritated sleep/delayed onset of sleep
b) Hypersomnia: Increased sleep, withdrawal from reality.
4. Psychomortor retardation or agitation: Reflected on motor behaviour, clumsiness of posture or gait, low self image, reduced volume of voice.
5. Loss of energy: Continued state of fatigue.
6. Feelings of worthlessness, hopelessness and helplessness, associated with inappropriate guilt, which often leads to narcissistic injury.
7. Defense mechanism used is mainly introjection.
8. Thought difficulty or cognitive errors are present.
9. Morbid thoughts: Recurrent thought of death and suicide.
10. Loss of Libido: Reduced sexual needs or loss of ability to enjoy sexual activity
11. Co-morbid anxiety and diurnal clock variation is evident.