This is a general term used to describe the illness of depression, which affects how a person feels, thinks, and manages daily life. For a broader understanding of what depression is, including its symptoms, causes, and impact, you can find more information on our About Depression page.

Depression occurring at a particular time of year or during a specific season. This is most commonly experienced in winter due to a lack of sunlight.

Postnatal depression (PND) is an illness affecting up to 15% of mothers. About one-third of these will have developed the symptoms during pregnancy. These symptoms include tiredness, anxiety and irritability, but with PND, there may not be strong feelings of sadness or unhappiness. This may mean that those affected don't seek help as they believe it is a result of sleep loss and coping with the demands of a new baby.

It is different from the 'Baby Blues' in that these are experienced by about 60% of women, usually starting on the third day after birth. Symptoms include feeling tearful and/or irritable for no apparent reason. These are due to hormonal changes and for most women last only one or two days, but no longer than 10 days. PND generally starts a few weeks after the birth and lasts longer.

For more information and support visit our Wellbeing During Pregnancy page.

Bipolar disorder (previously known as manic-depression) is a serious illness, and those affected may experience depression lasting weeks or months, alternating with bouts of elation or mania ('highs') of variable duration.

For more information and support, visit our Bipolar page.

Psychotic depression is a severe form of the illness where, in addition to the other common symptoms, those affected may lose contact with reality and experience hallucinations or delusions.