The following are the symptoms of severe depression:

• Depressed peoples are in a ceaseless low mood which seems to encompass all aspects of life. They no longer enjoy the activities they used to in the past. This inability to experience pleasure points to their disinterest in the world around them.
• They remain preoccupied with feelings and thoughts of regret, inappropriate guilt, hopelessness, worthlessness and self-hatred.
• Often, signs of psychosis are observed in cases of extremely severe depression. People begin to hallucinate and are deluded.
• Depressed people withdraw themselves from the social scene. They avoid social situations and activities and experience immense loneliness. They exhibit poor concentration and memory seems to become short spanned.
• Other common symptoms are reduced sex-drive, loss of appetite and consequent weight loss, lethargy, forgetfulness, headache, fatigue, digestive problems and thoughts of death or suicide.
• Changes in sleeping patterns may be a result of depression. Insomnia is lack of sleep and is a common symptom of depression. Hypersomnia is not as prevalent as insomnia although it is a symptom too.
• Children have somewhat different symptoms of depression. Instead of withdrawing from their normal activities, they tend to become hyper active, irritable, unreasonably demanding and insecure. Decline in academic performance and loss of interest in school are important signs of severe depression in children.