Bipolar disorder is divided into several subtypes. Each has a different pattern of symptoms. Types of bipolar disorder include:
- Bipolar I disorder. Mood swings with bipolar I cause significant difficulty in your job, school or relationships. Manic episodes can be severe and dangerous.1
- Bipolar II disorder. With bipolar II, you may have an elevated mood, irritability and some changes in your functioning, but generally you can carry on with your normal daily routine. Instead of full-blown mania, you have hypomania — a less severe form of mania. In bipolar II, periods of depression typically last longer than periods of hypomania.1
- Cyclothymic disorder. Cyclothymic disorder, also known as cyclothymia, is a mild form of bipolar disorder. With cyclothymia, hypomania and depression can be disruptive, but the highs and lows are not as severe as they are with other types of bipolar disorder. To be diagnosed, one must experience hypomanic episodes alternating with mild periods of depression for at least two years.1 1
- Bipolar Disorder Not Otherwise Specified (BP-NOS) is diagnosed when a person has symptoms of the illness that do not meet diagnostic criteria for either bipolar I or II. The symptoms may not last long enough, or the person may have too few symptoms, to be diagnosed with bipolar I or II. However, the symptoms are clearly out of the person’s normal range of behavior.2
Bipolar disorder often develops in a person’s late teens or early adult years. At least half of all cases start before age 25.1 Some people have their first symptoms during childhood, while others may develop symptoms late in life.
Bipolar disorder tends to worsen if it is not treated. Over time, a person may suffer more frequent and more severe episodes than when the illness first appeared.5 Also, delays in getting the correct diagnosis and treatment make a person more likely to experience personal, social, and work-related problems.6
Proper diagnosis and treatment helps people with bipolar disorder lead healthy and productive lives. In most cases, treatment can help reduce the frequency and severity of episodes.
Manic phase of bipolar disorder
Signs and symptoms of the manic or hypomanic phase of bipolar disorder can include:
- Inflated self-esteem1
- Poor judgment1
- Rapid speech1
- Racing thoughts1
- Aggressive behavior1
- Agitation or irritation1
- Increased physical activity1
- Risky behavior1
- Increased sex drive1
- Decreased need for sleep1
- Easily distracted1
- Careless or dangerous use of drugs or alcohol1
- Frequent absences from work or school1
- Delusions or a break from reality (psychosis)1
- Poor performance at work or school1
- Increasing goal-directed activities, such as taking on new projects2
- Being restless2
- Having an unrealistic belief in one’s abilities2
- Behaving impulsively and taking part in a lot of pleasurable,
high-risk behaviors, such as spending sprees, impulsive sex, and impulsive business investments.2
Depressive phase of bipolar disorder1
Signs and symptoms of the depressive phase of bipolar disorder can include:
- Suicidal thoughts or behavior
- Sleep problems
- Low appetite or increased appetite
- Loss of interest in activities once considered enjoyable
- Chronic pain without a known cause
- Frequent absences from work or school
- Poor performance at work or school
Hypomania. Some people with bipolar disorder experience hypomania. During hypomanic episodes, a person may have increased energy and activity levels that are not as severe as typical mania, or he or she may have episodes that last less than a week and do not require emergency care. A person having a hypomanic episode may feel very good, be highly productive, and function well. This person may not feel that anything is wrong even as family and friends recognize the mood swings as possible bipolar disorder. Without proper treatment, however, people with hypomania may develop severe mania or depression.2
Rapid cycling bipolar disorder. Some people with bipolar disorder have rapid mood shifts. This is defined as having four or more mood swings within a single year. However, in some people mood shifts occur much more quickly, sometimes within just hours.1
Mixed state. During a mixed state, symptoms often include agitation, trouble sleeping, major changes in appetite, and suicidal thinking. People in a mixed state may feel very sad or hopeless while feeling extremely energized.2
Psychosis. Sometimes, a person with severe episodes of mania or depression has psychotic symptoms too, such as hallucinations or delusions. The psychotic symptoms tend to reflect the person’s extreme mood. For example, psychotic symptoms for a person having a manic episode may include believing he or she is famous, has a lot of money, or has special powers. In the same way, a person having a depressive episode may believe he or she is ruined and penniless, or has committed a crime. As a result, people with bipolar disorder who have psychotic symptoms are sometimes wrongly diagnosed as having schizophrenia, another severe mental illness that is linked with hallucinations and delusions.2
The exact cause of bipolar disorder is unknown, but several factors seem to be involved in causing and triggering bipolar episodes:
- Biological differences. People with bipolar disorder appear to have physical changes in their brains. The significance of these changes is still uncertain but may eventually help pinpoint causes.
- Neurotransmitters. An imbalance in naturally occurring brain chemicals called neurotransmitters seems to play a significant role in bipolar disorder and other mood disorders.
- Hormones. Imbalanced hormones may be involved in causing or triggering bipolar disorder.
- Inherited traits. Bipolar disorder is more common in people who have a blood relative (such as a sibling or parent) with the condition. Children with a parent or sibling who has bipolar disorder are four to six times more likely to develop the illness, compared with children who do not have a family history of bipolar disorder. Researchers are trying to find genes that may be involved in causing bipolar disorder.
- Environment. Stress, abuse, significant loss or other traumatic experiences may play a role in bipolar disorder.