Depression is a mood disorder that involves a persistent feeling of sadness and loss of interest. It is different from the mood fluctuations that people regularly experience as a part of life.
Major life events, such as bereavement or the loss of a job, can lead to depression. However, doctors only consider feelings of grief to be part of depression if they persist.
Depression is an ongoing problem, not a passing one. It consists of episodes during which the symptoms last for at least 2 weeks. Depression can last for several weeks, months, or years.
The symptoms of depression can include:
a depressed mood reduced interest or pleasure in activities once enjoyed a loss of sexual desire changes in appetite unintentional weight loss or gain sleeping too much or too little agitation, restlessness, and pacing up and down slowed movement and speech fatigue or loss of energy feelings of worthlessness or guilt difficulty thinking, concentrating, or making decisions recurrent thoughts of death or suicide, or an attempt at suicide