Bipolar disorder, also known as bipolar affective disorder, is a mood disorder. Depending on your age, you may also be aware that it used to be called manic depression (and some people still prefer to use that term for their diagnosis). Bipolar is a chemical imbalance in the brain that prevents the body from regulating moods correctly. Which causes very extreme responses to stress:

  • Emotional
  • Physical
  • External stimuli – noise, light, smell

Resulting in intense mood and energy swings (depression & mania). It is estimated. That around 2% of the population are living with bipolar.* 

The majority of individuals who receive a diagnosis will be diagnosed with bipolar disorder, however some medical professionals may explain your illness in terms of a particular categorisation.

Bipolar 1

Individual’s mood swings move across the mood scale encompassing both manic episodes and depression. A diagnosis of bipolar I disorder means you will have had at least 1 episode of mania that lasts longer than 1 week. 90% of people will also have periods of depression. Untreated, manic episodes will generally last 3-6 months. Depressive episodes will generally last 6-12 months without treatment.

Bipolar 2

A diagnosis of bipolar II disorder means it is common to have symptoms of depression. You will have had at least 1 period of severe depression. And at least 1 period of hypomania instead of mania. The majority of individuals with bipolar II will experience hypomania (6 to 8 on the mood scale) rather than extreme manic episode (8 to 10 on the mood scale). 

Bipolar 1 or 2 disorder with mixed features

You may hear this being called ‘mixed bipolar state’. You will experience symptoms of mania or hypomania and depression at the same time, which may result in agitation, trouble sleeping and significant change in appetite, psychosis and suicidal thoughts. 

Bipolar 1 or 2 disorder with rapid cycling

Rapid cycling means you have had four or more depressive, manic, hypomanic episodes in a 12-month period. Rapid cycling affects around one in ten people with bipolar, and can happen with bipolar I and II. see also a separate FAQ: What is rapid cycling?

Bipolar 1 or 2 with seasonal pattern

Seasonal pattern means that either your depression, mania or hypomania is regularly affected in the same way by seasons. For example, you may find that each winter you have a depressive episode but your mania does not regularly follow a pattern. 


A diagnosis of cyclothymic disorder means you will have experienced regular episodes of hypomania and depression for at least 2 years, with no period longer than two months in which there has been a stable state and no mixed episodes. Although individuals diagnosed with cyclothymia are on the bipolar spectrum, they will not have a bipolar disorder diagnosis. Cyclothymia can however develop into bipolar disorder. 


Sometimes severe mania (8 to 10 on the mood scale) or depression (2 to 0 on the mood scale) is accompanied by periods of psychosis. Psychotic symptoms include hallucinations and delusions, sometimes referred to as messianic mania.

You can use our mood scale to help you describe your mood. The mood scale can also be used with our mood diary to help keep track of your moods. 


* Adult Psychiatric Morbidity Survey: Survey of Mental Health and Wellbeing, England, 2014

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