Bipolar disorder

What is bipolar disorder?

People who have bipolar disorder experience periods (or ‘episodes’) of mania and periods (or ‘episodes’) of depression. Bipolar disorder used to be called ‘manic depression’.

When people are unwell, they may experience the symptoms of psychosis – hallucinations and delusions, for example. However, not everyone who has bipolar disorder experiences psychosis, and psychotic symptoms are not necessary for a diagnosis of bipolar disorder to be given.

In most cases, people with bipolar disorder experience both episodes of mania and episodes of depression. Episodes of depression tend to be more common than episodes of mania.

Episodes of mania and depression may alternate with one another, but sometimes people have a mixture of the symptoms of mania and the symptoms of depression at the same time. When that happens, this is called a ‘mixed’ episode.

The frequency of episodes varies quite considerably: some people might have one episode a year while others have episodes more often. People can be very well in between episodes.

When people have at least four episodes of any kind within a year, mental health professionals say they have ‘rapid cycling’ bipolar disorder. 

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Bipolar 2 disorder

People may be given a diagnosis of bipolar 1 disorder or bipolar 2 disorder. People who have bipolar 2 disorder have episodes of depression and episodes involving less severe symptoms of mania. This is called ‘hypomania’ and is less likely to interfere dramatically with their lives. 

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Who gets bipolar disorder?

About one in every 100 people develops bipolar 1 disorder. The first episode usually occurs before the age of 30.

Bipolar 2 disorder is thought to be more common. The estimated numbers of people with bipolar 2 disorder may be as high as five in every 100 people.

Researchers still don’t know the precise causes of bipolar disorder, but there is strong evidence from twin and family studies to indicate that genes may have quite a large part to play.

Scientists know from research studies that first-degree relatives (children or brothers and sisters) of someone with bipolar disorder are much more likely to develop bipolar disorder themselves than people who have no bipolar in the family. First-degree relatives of someone with bipolar disorder also have a much higher risk of developing depression, schizophrenia and schizoaffective disorder.

Recent studies have suggested there are a number of specific genes involved in bipolar disorder, but each of these ‘risk genes’ on their own have quite small effects. Researchers think that people need to inherit many ‘risk genes’ – and even if they do inherit a lot of them, they won't necessarily go on to experience bipolar disorder because there are other factors that contribute to its development.

There is some evidence that people who are highly intelligent, or who are especially creative, may be more likely to develop bipolar disorder.

Scientists also think that the stress hormone cortisol, and the system in the brain that activates it (called the HPA – hypothalamic-pituitary-adrenal – axis) may have something to do with the development of both depression and bipolar disorder. Researchers have found higher than normal cortisol levels in people with depression (especially people who have psychotic depression), which might mean the HPA axis isn’t working properly. Some studies have also found abnormalities in this system in people with bipolar disorder. If cortisol levels are high all the time, this has an effect on mood and memory.

There have also been studies that have found abnormalities in the system that regulates thyroid hormones in people with bipolar disorder. The system is called the HPT – hypothalamic-pituitary-thyroid – axis. Thyroid hormones can affect mood and behaviour.

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During the early stages of a manic episode, people can be very happy, productive and creative. They have less need for sleep and don’t feel tired.

However, the energetic and high mood then gets out of control. Even if they are physically exhausted, people have no desire to rest. They can become overactive, irritable and restless, finding it hard to be still and difficult to concentrate. They may feel over-confident, believing they can do anything, and come up with extravagant ideas and wild or grandiose plans.

They begin to lose judgement, take risks and become impulsive. These risks can lead to bad decisions – bouts of spending that cause financial problems, for example. Their libido may rise and they may become promiscuous. They may talk or shout quickly and loudly. They may be difficult to understand because their thoughts and ideas are coming thick and fast. They may begin to drink a lot of alcohol or use more street drugs.

They may begin to experience the symptoms of psychosis – delusions, hallucinations and confused thoughts. People who have the symptoms of psychosis may believe they are getting special messages, or that someone is trying to thwart their plans.

When people are experiencing mania, they don’t see that they are unwell or need treatment. Because people’s behaviour is so extreme, they sometimes need to be admitted to hospital for treatment.

An episode of mania can last for a few days or for a few months. Afterwards, people are often completely worn out and may feel ashamed of and humiliated by their behaviour.

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The depression experienced by people with bipolar disorder is similar to major or severe depression – what mental health professionals call ‘unipolar’ depression.

People lose interest in their daily lives, feel very low, get very tired, put on or lose weight, have disrupted sleep patterns (finding it hard to sleep or difficult to stay awake), feel worthless and useless. They may experience delusions – feeling they are totally to blame for bad events in the world, for example – or hallucinations.

People often think about harming themselves or attempt to take their own lives during episodes of depression. About 17 per cent of people with bipolar 1 and 24 per cent of people with bipolar 2 attempt suicide. Most of these attempts are made when they are experiencing an episode of depression, which can last for several months. 

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Sometimes it may be difficult to diagnose bipolar disorder, especially after a first episode. If the first episode is depression, it can be hard to work out if someone has unipolar depression or will go on to develop bipolar disorder. The symptoms of mania may be caused by other conditions, by prescribed medication or by street drugs, and doctors will need to rule out these out as a possibility. 

An online survey of people who have bipolar disorder and their families (carried out by Bipolar UK, Bipolar Scotland and the Royal College of Psychiatrists in 2012) showed that many people were not diagnosed for more than 13 years after they had first started experiencing symptoms. 15 per cent of more than 700 people surveyed had been diagnosed promptly but 85 per cent had difficulty getting the right diagnosis – most were initially wrongly diagnosed with depression.

When making a diagnosis, mental health professionals should assess people’s symptoms and find out if there have been previous episodes of depression or mania, and whether any family members have had bipolar disorder. 

There are two systems of classification to help mental health professionals make a diagnosis.

The first is the Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association.

The second is the International Classification of Disease (ICD), published by the World Health Organisation.

The definition of bipolar disorder is similar in each one. However, the current version of the ICD does not include bipolar 2 disorder. Only the DSM talks about bipolar 2 disorder, where people experience episodes of depression and less severe mania symptoms called hypomania. It also includes ‘cylothymia’ which is when someone has episodes of hypomania and less severe episodes of depression (see Mental health diagnoses page).

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Treatment and care

People may be cared for by a GP alone or, more commonly, by a GP and a mental health team.

Different sorts of drugs are prescribed for episodes of mania and episodes of depression and many people need to take medication on a regular basis, even when they are well, to help prevent relapse. Medication prescribed for long-term treatment to prevent relapse is called 'prophylactic' medication.

Talking therapies like cognitive behaviour therapy and family therapy may also be offered to help stabilise people’s mood and help them recognise early symptoms so they can try to prevent new episodes.

ECT (electroconvulsive therapy) is occasionally offered to people who have bipolar disorder if medication is not working, and if someone has very severe symptoms, including the symptoms of psychosis.

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The drugs that may be prescribed for mania are antipsychotics (such as olanzapine, quetiapine or risperidone), and ‘mood stabilisers’ (such as lithium or valproate) (see Medication for bipolar disorder page). Valproate should not be prescribed for women who are, or who may become pregnant, as it could harm the baby. 

People who are prescribed lithium need to have regular blood tests to make sure the levels of the drug inside their body do not become too high. Lithium is the most effective mood stabiliser but too much can be poisonous.

Doctors may also prescribe a benzodiazepine (a sedative and muscle relaxant) to help people calm down and sleep better.

During an episode of depression, people may be prescribed an antidepressant to take only until the symptoms of depression are gone. They may also be prescribed antipsychotic medication. Sometimes, antidepressants can start an episode of mania, so people may also be prescribed a drug for mania, if they are not already taking one.

If people experience the symptoms of psychosis, the doctor may prescribe antipsychotic medication in addition to other treatment.

If people experience a mixed episode, they will be given medication for mania, but not usually an antidepressant.

The National Institute for Health and Care Excellence (NICE) recommends that for long-term treatment, doctors offer the same type of medication used for manic episodes – lithium, valproate or the antipsychotic olanzapine. Sometimes people are prescribed a combination of the drugs. One large trial showed that either a combination regime of lithium and valproate, or lithium alone, was more effective over two years than valproate on its own.

People may also be prescribed mood stabilising drugs lamotrigine or carbamazepine for long-term treatment.

People should not continue on antidepressants in the long-term – there is no evidence that antidepressants help prevent relapse.

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Physical health

The medication used to treat bipolar disorder can affect people’s physical health – one of the side effects may be weight gain, for example, which can contribute to other physical health problems.

The National Institute for Health and Care Excellence (NICE) guidelines on bipolar disorder say people should be given a physical health check once a year to make sure any problems are picked up and treated.

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Pregnancy and birth

Women who have been given a diagnosis of bipolar disorder might experience a relapse of the illness almost immediately after the birth of their first child. This is called puerperal, or postpartum, psychosis. Women who experience puerperal psychosis after the birth of their first child will almost inevitably experience it again following the birth of a second child, and after subsequent births (see New mothers (puerperal psychosis) page).

It is very important for women to tell doctors if they become pregnant, or if they are trying for baby. Women should discuss the possibility of experiencing puerperal psychosis with their psychiatrist and obstetrician: ideally, they should talk to their psychiatrist before they become pregnant. Some medication prescribed for bipolar disorder should not be taken during pregnancy as it may harm the developing baby. Women may therefore need to change medication during pregnancy and their psychiatrist will advise on alternative drugs.

It is also important to plan support and care after the birth. The risk of puerperal psychosis is highest straight after birth, so health professionals may arrange for women to stay for a few days longer on an obstetric ward, for example, where support from a hospital-based psychiatrist is available at all hours.

In many parts of the country, there are dedicated perinatal psychiatry teams who can give expert advice about preventative measures and can help coordinate care of women who are at risk of developing puerperal psychosis.

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Other diagnoses

Some people with bipolar disorder have other mental health problems at the same time. Mental health professionals call these ‘comorbid’ problems.

Between 30 to 50 per cent of people with bipolar disorder experience anxiety, or use drugs and/or alcohol in a way that is detrimental to their health.

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Living with bipolar disorder

The majority of people with bipolar disorder get recurrent episodes. In between episodes, however, most people don’t experience any symptoms.

Manic episodes can be very disruptive to everyday life and can also be dangerous – they can lead to dangerous driving, financial problems, high-risk sexual behaviour, legal challenges or loss of a job, for example.

People can often identify changes in their mood or behaviour that might indicate the start of another episode. Knowing what these warning signs are, of whether there are any triggers for relapse, can be helpful to the individual who is unwell, and also to their family members and friends.

The National Institute for Health and Care Excellence (NICE) guidance on bipolar disorder says health professionals should give family members information about the illness and treatments that are offered, and should be available to help and advise at times of crisis. Families should also be involved in assessment and treatment plans.



This page was last updated 13 December 2012 (NICE name change incorporated 3 April 2013).
Links on this page last checked: 27 July 2014
Next links check due: December 2014