Depression is more than simply feeling unhappy or fed up for a few days. Most people go through periods of feeling down, but when you're depressed you feel persistently sad for weeks or months, rather than just a few days. Some people think depression is trivial and not a genuine health condition.
Read about the symptoms of depression, which can be mild, moderate or severe. Symptoms can also be classed as psychological, physical and social.
Read about what causes depression. There's no single cause and many possible risk factors.
Find out how depression is diagnosed. Your GP will ask you lots of questions about your general health and how your feelings are affecting you mentally and physically.
Find out how depression is treated. Treatment depends on how severe your depression is, but usually involves a combination of self-help, talking therapies and medication.
Information and advice about coping with depression, including diet and exercise, talking therapy, dealing with bereavement and caring for someone who's depressed.
Read about psychotic depression, a severe form of depression where people experience the usual symptoms of depression, plus delusions and hallucinations.
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