Various terms are used in an attempt to classify depression, particularly for the purpose of medical diagnoses. However, there are not different types of depression as such, only varying degrees of it, so these terms generally refer to its severity, duration and possible causes.
Major depressive disorder
This is a severe depression that has continued for at least two weeks and affects a person’s life and daily activities to the extent that they cannot function normally at all. Some people experience a major depressive episode only once but for others it recurs.
This is a medical term used to describe mild to moderate depression that is chronic and has persisted for at least two years. Those suffering from dysthymia are able to function just about adequately but feel low all the time and find little pleasure in life.
Also known as postpartum depression, this may develop up to a year after giving birth. It differs from the ‘baby blues’, which many new mothers experience for a short time, in that it lasts much longer, is often more severe and can be accompanied by extreme anxiety.
Seasonal affective disorder
Appropriately given the acronym SAD, this is sometimes called winter depression. It comes on seasonally when daylight hours reduce substantially and goes off as the days lengthen, with symptoms usually abating by springtime.
This term may be used to describe depression brought on by bereavement, relationship breakdown, job loss, financial problems, or other traumatic events and difficult situations. Alternatively, it may be referred to as reactive depression.
Previously known as manic depression, bipolar disorder is marked by extreme mood swings. Emotions veer wildly from elation and euphoria, with a very high level of motivation and physical energy, to deep depression and utter despair, accompanied by lethargy and exhaustion.
A person experiencing severe depression and anxiety, together with mental and physical exhaustion, to the extent that they can no longer cope, is commonly said to have suffered a nervous breakdown. This may also be called adrenal exhaustion or burnout.
This word is from the Greek for sadness. Its use in the medical sense dates back to the time of Hippocrates, when it described a deep depression. Today, melancholic depression is a term occasionally used to denote a form of major depressive disorder.