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Bipolar Disorder

(Manic-Depressive Disorder)


William Coryell

, MD, Carver College of Medicine at University of Iowa

Last full review/revision Mar 2020| Content last modified Mar 2020

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

  • 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.
  • Drugs that stabilize mood, such as lithium and certain antiseizure drugs, and sometimes psychotherapy can help.

Bipolar disorder is so named because it includes the two 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

  • 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 depressive episodes.
  • Bipolar II disorder: People have had major depressive episodes, 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 physical disorders and drugs can cause symptoms of bipolar disorder.
  • People experiencing mania often think they are in their best form.

Causes of Bipolar Disorder

The exact cause of bipolar disorder is not known. Heredity is thought to be involved in the development of bipolar disorder. Also, 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 in certain other disorders, such as high levels of thyroid hormone (hyperthyroidism). Also, manic episodes may be caused or triggered by drugs, such as cocaine and amphetamines.

Some Causes of Mania



Brain and nervous system disorders

Brain tumors

Head injury

Huntington disease

Multiple sclerosis

Seizures that affect the temporal lobe (complex partial seizures)


Connective tissue disorders

Rheumatic fever

Systemic lupus erythematosus (lupus)



Encephalitis due to certain viral infections


Syphilis (late stage)

Hormonal disorders

High levels of thyroid hormones (hyperthyroidism)



Certain antidepressants (including tricyclic antidepressants and monoamine oxidase inhibitors)





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 four or more episodes each year (called rapid cycling). Despite this large variation, the cycle time for each person is relatively consistent.

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

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


Depression in bipolar disorder resembles depression that occurs alone. People 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 to 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 feel exuberant, energetic, and elated or irritable. They may also feel overly confident, act or dress extravagantly, sleep little, 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 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 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
  • Sometimes blood and urine tests to rule out other disorders

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 drugs being taken to check whether any could contribute to the symptoms. Doctors may also check for signs of other disorders 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 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

  • Drugs
  • 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

  • Drugs to stabilize mood (mood stabilizers), such as lithium and some antiseizure drugs
  • Antipsychotic drugs
  • 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 can lessen the symptoms of mania and depression. Lithium helps prevent mood swings in many people with bipolar disorder. Because lithium takes 4 to 10 days to work, a drug that works more rapidly, such as an antiseizure or a newer (second-generation) antipsychotic drug, is often given to control excited thought and activity.

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.

Lithium toxicity 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 people
  • 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 must stop taking lithium because rarely, lithium can cause heart defects in a developing fetus.

Antiseizure drugs

The antiseizure drugs valproate and carbamazepine 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 lithium, these drugs do not damage the kidneys. However, carbamazepine can greatly reduce the number of red and white blood cells. Rarely, valproate damages the liver (primarily in children) or severely damages the pancreas. With close monitoring by a doctor, these problems can be caught in time. Valproate is usually not prescribed for women with bipolar disorder if they are pregnant or of childbearing age because the drug 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.

Lamotrigine 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 drug 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 three days or more, the schedule for gradually increasing the dose must begin again.


Sudden manic episodes are increasingly treated with second-generation antipsychotics because they act quickly and the risk of serious side effects is less than that with other drugs used to treat bipolar disorder. These drugs include aripiprazole, lurasidone, olanzapine, quetiapine, risperidone, ziprasidone, and cariprazine.

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 ( insulin resistance), a high blood sugar level, abnormal cholesterol levels, and high blood pressure. The risk of this syndrome may be lower with aripiprazole and ziprasidone.


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


Psychotherapy is often recommended for people taking mood-stabilizing drugs, 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 drugs used to treat the disorder can help people take them as directed. People may resist taking the drugs because they believe that these drugs 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.

People should learn how to recognize symptoms as soon as they start, as well as learn ways to help prevent symptoms. For example, avoiding stimulants (such as caffeine and nicotine) and alcohol can help, as can getting enough sleep.

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 marriage 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 about Bipolar Disorder

  • Depression and Bipolar Support Alliance (DBSA), Bipolar Disorder: General information on bipolar disorder, including access to crisis lines and support groups
  • Mental Health America (MHA), Bipolar Disorder: General information on bipolar disorder, including an explanation of diagnoses and other terms associated with bipolar disorder
  • National Alliance on Mental Illness (NAMI), Bipolar Disorder: General information on bipolar disorder, including its causes, symptoms, diagnosis, and treatment
  • 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

Drugs Mentioned In This Article

Generic Name Select Brand Names
carbamazepine TEGRETOL
Bromocriptine PARLODEL
aripiprazole ABILIFY
ziprasidone GEODON
Lamotrigine LAMICTAL
risperidone RISPERDAL
cariprazine VRAYLAR
lurasidone LATUDA
quetiapine SEROQUEL
olanzapine ZYPREXA
Levodopa Levodopa
lithium LITHOBID

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