Depression is viewed as a whole-body diagnosis, involving mood, mind, physical health, and interpersonal functioning. It affects the way a person thinks, feels, behaves, and functions on a daily basis for a period of time (typically two weeks or longer). The common symptoms include the following:
- A persistent sad, down or "empty" mood
- Crying or getting angry easily
- Sleeping too little, early morning awakening, or sleeping too much
- Reduced appetite and weight loss, or increased appetite and weight gain
- Loss of interest or pleasure in activities once enjoyed
- Restlessness or irritability
- Difficulty concentrating, remembering, or making decisions
- Fatigue or loss of energy
- Aches and pains that do not go away
- Social isolation and withdrawal
- Loss of direction, meaning, or purpose
- Thoughts of death or suicide
- Feelings of worthlessness or guilt
- Low self-esteem