Bipolar Disorder

(Manic-Depressive Disorder)

ByWilliam Coryell, MD, University of Iowa Carver College of Medicine
Reviewed/Revised Oct 2023

In bipolar disorder (formerly called manic-depressive disorder), episodes of depression alternate with episodes of mania (or a less severe form of mania called hypomania). Mania is characterized by excessive feelings of elation and confidence or physical activity that are greatly out of proportion to the situation, and people may engage in risky behaviors.

(See also Overview of Mood Disorders.)

  • Heredity probably plays a part in bipolar disorder.

  • Episodes of depression and mania may occur separately or together.

  • People have one or more periods of excessive sadness and loss of interest in life and one or more periods of elation, extreme energy, and often irritability, with periods of relatively normal mood in between.

  • Doctors base the diagnosis on the pattern of symptoms.

The name bipolar disorder is based on the shift in moods between 2 extremes, or poles, of mood disordersdepression and mania. It affects about 4% of the U.S. population to some degree. Bipolar disorder affects men and women equally. Bipolar disorder usually begins in a person’s teens, 20s, or 30s. Bipolar disorder in children is rare.

Most bipolar disorders can be classified as either

  • Bipolar I disorder: People have had at least one full-fledged manic episode (one that prevents them from functioning normally or that includes delusions) and usually have also had depressive episodes.

  • Bipolar II disorder: People have had major depressive episodes and at least one less severe manic (hypomanic) episode, but no full-fledged manic episodes.

However, some people have episodes that resemble a bipolar disorder but are milder and do not meet the specific criteria for bipolar I or II disorder. Such episodes may be classified as an unspecified bipolar disorder or cyclothymic disorder.

Did You Know...

  • Certain general medical conditions, medications, and illicit drugs can cause symptoms similar to those of bipolar disorder.

Causes of Bipolar Disorder

The exact cause of bipolar disorder is not known. Heredity is thought to be involved in the development of this disorder. Also, in people with bipolar disorder, certain substances the body produces, such as the neurotransmitters norepinephrine or serotonin, may not be regulated normally. (Neurotransmitters are substances that nerve cells use to communicate.)

Bipolar disorder sometimes begins after a stressful event, or such an event triggers another episode. However, no cause-and-effect relationship has been proved.

The manic symptoms in bipolar disorder can occur for other reasons, such as certain illnesses, such as high levels of thyroid hormone (hyperthyroidism). Also, manic episodes may be caused or triggered by medications (such as corticosteroids) or illicit drugs (such as and amphetamines).


Symptoms of Bipolar Disorder

In bipolar disorder, episodes of symptoms alternate with virtually symptom-free periods (remissions). Episodes last anywhere from a few weeks to 3 to 6 months. Cycles—time from onset of one episode to that of the next—vary in length. Some people have infrequent episodes, perhaps only a few over a lifetime, whereas others have 4 or more episodes each year (called rapid cycling). Despite this large variation, the cycle time for each person is relatively consistent.

Mental Health Myths

Episodes consist of depression, mania, or less severe mania (hypomania). Only a minority of people alternate between mania and depression during each cycle. In most, one or the other predominates to some extent.

People with bipolar disorder may attempt or complete suicide. Over their lifetime, they are at least 15 times more likely to complete suicide than the general population.


Depression in bipolar disorder resembles depression that occurs alone. People with depression feel excessively sad and lose interest in their activities. They think and move slowly and may sleep more than usual. Their appetite may be increased or decreased, and they may gain or lose weight. They may be overwhelmed with feelings of hopelessness and guilt. They may be unable to concentrate or make decisions.

Psychotic symptoms (such as hallucinations and delusions) are more common in depression that occurs in bipolar disorder than in depression that occurs alone.


Episodes of mania end more abruptly than those of depression and are typically shorter, lasting a week or longer.

People with mania feel exuberant, noticeably more energetic, and elated or irritable. They may also feel overly confident, act or dress extravagantly, sleep very few hours, and talk more than usual. Their thoughts race. They are easily distracted and constantly shift from one theme or endeavor to another. They pursue one activity (such as risky business endeavors, gambling, or dangerous sexual behavior) after another, without thinking about the consequences (such as loss of money or injury). However, people often think that they are in their best mental state.

People with mania lack insight into their condition. This lack plus their huge capacity for activity can make them impatient, intrusive, meddlesome, and aggressively irritable when crossed. As a result, they may have problems with social relationships and may feel that they are being treated unjustly or are being persecuted.

Some people have hallucinations, hearing and seeing things that are not there.

Manic psychosis is an extreme form of mania. People have psychotic symptoms that resemble those present in schizophrenia. They may have extremely grandiose delusions, such as of being Jesus. Others may feel persecuted, such as being pursued by the Federal Bureau of Investigation (FBI). Activity level increases markedly. People may race about and scream, swear, or sing. Mental and physical activity may be so frenzied that there is a complete loss of coherent thinking and behavior (delirious mania), causing extreme exhaustion. People so affected require immediate treatment.


Hypomania is not as severe as mania. People feel cheerful, need little sleep, and are mentally and physically active.

For some people, hypomania is a productive time. They have a lot of energy, feel creative and confident, and often function well in social situations. They may not wish to leave this pleasurable state. However, other people with hypomania are easily distracted and easily irritated, sometimes resulting in angry outbursts. They often make commitments that they cannot keep or start projects that they do not finish. They rapidly change moods. They may recognize such effects and be bothered by them, as are the people around them.

Mixed episodes

When depression and mania or hypomania occur in one episode, people may momentarily become tearful in the middle of elation, or their thoughts may start racing in the middle of depression. Often, people go to bed depressed and wake early in the morning and feel elated and energetic.

The risk of suicide during mixed episodes is particularly high.

Diagnosis of Bipolar Disorder

  • A doctor's evaluation, based on standard psychiatric diagnostic criteria

  • Sometimes blood and urine tests to rule out other general medical conditions and use of illicit drugs

The diagnosis of bipolar disorder is based on specific lists of symptoms (criteria). However, people with mania may not accurately report their symptoms because they do not think anything is wrong with them. So doctors often have to obtain information from family members. People and their family members can use a short questionnaire to help them evaluate the risk of bipolar disorder (see Mood Disorder Questionnaire).

Doctors also ask people whether they have any thoughts about suicide.

Doctors review the medications being taken to check whether any could contribute to the symptoms. Doctors may also check for signs of other general medical conditions that may be contributing to symptoms. For example, they may do blood tests to check for hyperthyroidism and blood or urine tests to check for illicit drug use.

Doctors determine whether people are experiencing an episode of mania or depression so that the correct treatment can be given.

Treatment of Bipolar Disorder

  • Medications

  • Psychotherapy

  • Education and support

For severe mania or depression, hospitalization is often required. Even if mania is less severe, people may need to be hospitalized if they are suicidal, try to hurt themselves or others, cannot care for themselves, or have other serious problems (such as alcohol use or other substance use disorders). Most people with hypomania can be treated as outpatients. People with rapid cycling are more difficult to treat. Without treatment, bipolar disorder recurs in almost all people.

Treatment may include

  • Antipsychotic medications

  • Certain antidepressants

  • Psychotherapy

  • Education and support

  • Electroconvulsive therapy, which is sometimes used when mood stabilizers do not relieve depression

  • Phototherapy, which can be useful in treating seasonal bipolar disorder (which has some features in common with seasonal affective disorder)


Lithium helps prevent mood swings in many people with bipolar disorder. Because lithium takes 4 to 10 days to work, a medication that works more rapidly, such as an antiseizure or a newer (second-generation) antipsychotic medication, is often given to control excited thought and activity. People with a family history of typical bipolar disorders are more likely to respond to lithium.

Lithium can have side effects. It can cause drowsiness, confusion, involuntary shaking (tremors), muscle twitching, nausea, vomiting, diarrhea, thirst, excessive urination, and weight gain. It often worsens a person's acne or psoriasis. However, these side effects are usually temporary and are often lessened or relieved when doctors adjust the dose. Sometimes lithium must be stopped because of side effects, which then resolve.

Doctors monitor the level of lithium in the blood with regular blood tests because if levels are too high, side effects are more likely. Long-term use of lithium can cause low levels of thyroid hormone (hypothyroidism) and can impair kidney function. Therefore, thyroid and kidney function must be monitored with regular blood tests, and the lowest effective dose is used.

occurs when the level of lithium in the blood is very high. It causes persistent headaches, mental confusion, drowsiness, seizures, and abnormal heart rhythms. Toxicity is more likely to occur in the following:

  • Older adults

  • People with impaired kidney function

  • People who have lost a lot of sodium through vomiting, diarrhea, or use of diuretics (which make the kidneys excrete more sodium and water in urine)

Women who are trying to become pregnant or are pregnant must stop taking lithium because rarely, lithium can cause heart defects in a developing fetus.

Antiseizure medications

The antiseizure medications valproate and act as mood stabilizers. They may be used to treat mania when it first occurs or to treat mania and depression when they occur together (mixed episode). Unlike lithiumValproate is usually not prescribed for women with bipolar disorder if they are pregnant or of childbearing age because the medication appears to increase the risk of brain or spinal cord birth defects (neural tube defects), attention-deficit/hyperactivity disorder, and autism in the fetus. Valproate and carbamazepine can be useful, especially when people have not responded to other treatments.

is sometimes used to help control mood swings and treat depression. Lamotrigine can cause a serious rash. Rarely, the rash becomes the life-threatening Stevens-Johnson syndrome. People who are taking lamotrigine should watch for any new rash (particularly in the area around the rectum and genitals), fever, swollen glands, blistering sores in the mouth or on the eyes, and swelling of the lips or tongue. They should report these symptoms to the doctor. To reduce the risk of developing these symptoms, doctors carefully follow the recommended schedule for increasing the dose. The medication is started at a relatively low dose, which is increased very slowly (over a period of weeks) to the recommended maintenance dose. If doses are interrupted for 3 days or more, the schedule for gradually increasing the dose must begin again.


Sudden manic episodes are increasingly treated with second-generation antipsychotics

For bipolar depression, certain antipsychotics may be the best choice. Some of them are given with an antidepressant.

Long-term side effects of antipsychotics may include weight gain and the metabolic syndrome. Metabolic syndrome is excess fat in the abdomen with reduced sensitivity to insulin’s effects (insulinrisperidone, which has been associated with a small increase the risk of birth defects.

Certain antidepressants are sometimes used to treat severe depression in people with bipolar disorder, but their use is controversial. Therefore, these medications are used only for short periods and usually are given along with a mood-stabilizing medication or an atypical antipsychotic.

Other treatments

Electroconvulsive therapy (ECT—sometimes known as "shock therapy") is sometimes used for treatment-resistant depression and mania. 

Phototherapy, in which people look at bright lights that simulate sunlight, can be useful in treating seasonal (with autumn-winter depression and spring-summer hypomania) or nonseasonal bipolar I or bipolar II disorder. It is probably most useful when used to supplement other treatments. 

Transcranial magnetic stimulation, in which a device applies a harmless magnetic field to the head, used in the treatment of severe, resistant depression, has also proven effective in the treatment of bipolar depression.


Psychotherapy is often recommended for people taking mood-stabilizing medications, mostly to help them take their treatment as directed.

Group therapy often helps people and their partners or relatives understand bipolar disorder and its effects.

Individual psychotherapy may help people learn how to better cope with problems of daily living.

Education and support

Learning about the effects of the medications used to treat the disorder can help people take them as directed. People may resist taking the medications because they believe that these medications make them less alert and creative. However, decreased creativity is relatively uncommon because mood stabilizers usually enable people to function better at work and school and in relationships and artistic pursuits.

Doctors or therapists may talk to people about the consequences of their actions. For example, if people are inclined to sexual excesses, they are given information about how their actions can affect their relationships and about health risks of promiscuity, particularly AIDS. If people tend to be financially extravagant, they may be advised to turn their finances over to a trusted family member.

It is important for family members to understand bipolar disorder, be involved in treatment, and provide support.

Support groups can help by providing a forum to share common experiences and feelings.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  1. Depression and Bipolar Support Alliance (DBSA), Bipolar Disorder: General information on bipolar disorder, including access to crisis lines and support groups

  2. Mental Health America (MHA), Bipolar Disorder: General information on bipolar disorder, including an explanation of diagnoses and other terms associated with bipolar disorder

  3. National Alliance on Mental Illness (NAMI), Bipolar Disorder: General information on bipolar disorder, including its causes, symptoms, diagnosis, and treatment

  4. National Institutes of Mental Health (NIMH), Bipolar Disorder: General information on many aspects of bipolar disorder, including treatment and therapies, educational materials, and information on research and clinical trials

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