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Types of depression

Last Update: June 18, 2020; Next update: 2023.

There are different types of depression, with different levels of severity. Some only arise under certain circumstances, for example after giving birth.

Doctors differentiate between the following types of depression, based on the symptoms and possible causes:

Unipolar depression

This is the most common form of depression. People experience several typical symptoms such as feeling down, exhausted, gloomy and lacking motivation for at least two weeks. They may also have trouble sleeping and lose their appetite. Depending on how many symptoms a person has and how bad they are, depression is classed as mild, moderate or severe.


Some people have a less severe mood disorder that is similar to depression. They feel unsettled, unhappy and down, but this doesn't affect their everyday lives as much as depression does. The symptoms change from day to day and week to week. If the symptoms last for at least two years, it is considered to be a chronic depressive disorder called dysthymia. Although the symptoms are less severe than they are in typical depression, dysthymia can be just as distressing because it lasts so long. If people with dysthymia have an episode of depression as well, it is referred to as “double depression.”

Seasonal affective disorder (SAD)

Some people are particularly affected by depression in the dark autumn and winter months. It is mainly caused by the lack of light at this time of year. This kind of depression is referred to as seasonal affective disorder, or SAD for short. It usually goes away again in the spring.

Postnatal depression

Many mothers experience inexplicable mood swings and feel down after childbirth. In some women, these “baby blues” turn into what is referred to as postnatal or postpartum depression. The symptoms are much the same as those of clinical depression at any other time of life.

Postnatal depression is sometimes so severe that mothers have trouble looking after their child. And they often get the impression that those around them don’t understand how they can feel so down after becoming a mother. People generally expect mothers to be happy after the birth of a child. This can often lead to mothers feeling very guilty, about not being there for their baby too.

Bipolar disorder

Depression is sometimes part of a condition known as bipolar disorder or manic depression. People who have bipolar disorder experience alternating phases involving extreme mood swings. In one phase they have the typical symptoms of depression. In the other phase their mood changes completely: All of a sudden they feel on top of the world, are very excitable and extremely active, as well as being self-confident to the point of becoming delusional. They overflow with ideas, but are scatterbrained and often don’t sleep much. During these euphoric (“manic”) phases, many people lose touch with reality and start imagining things. They might get themselves into trouble, for instance due to impulsive, risky behavior or by getting into a lot of debt.


  • Deutsche Gesellschaft für Psychiatrie und Psychotherapie, Psychosomatik und Nervenheilkunde (DGPPN). S3-Leitlinie und Nationale Versorgungsleitlinie (NVL): Unipolare Depression. AWMF-Registernr.: nvl-005. March 2017.
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