Patients & CaregiversHealthcare ProfessionalsWorldwide
HomeAbout MerckProductsNewsroomInvestor RelationsCareersResearchLicensingThe Merck Manuals
THE MERCK MANUAL MEDICAL LIBRARY: The Merck Manual of Medical Information--Home Edition
Tips for better results
ABCDEFGHI
JKLMNOPQR
STUVWXYZ

Section

Subject

Topics

Bipolar Disorder (Manic-Depressive Illness)

Pronunciations

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.
  • Periods of excessive sadness and loss of interest in life alternate with periods of elation, extreme energy, and often irritability, with periods of relatively normal mood in between.
  • Doctors based the diagnosis on the pattern of symptoms.
  • Drugs that stabilize mood, such as lithium Some Trade Names
    LITHANE
    LITHONATE
    and certain antiseizure drugs, and sometimes psychotherapy can help.

Bipolar disorder is so named because it includes the two extremes, or poles, of mood disorders—depression and mania. It affects slightly less than 4% of the U.S. population to some degree. Bipolar disorder affects men and women equally. However, women are more likely to have symptoms of depression, and men are more likely to have symptoms of mania. Bipolar disorder usually begins in a person's teens, 20s, or 30s.

Bipolar disorders are classified as

  • Bipolar I disorder: People have had at least one manic episode and usually depressive episodes
  • Bipolar II disorder: People have had major depressive episodes, at least minor manic (hypomanic) episode, but no full manic episodes

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

Hereditary is thought to be involved in the development of bipolar disorder. Abnormal levels of certain substances the body produces, such as the neurotransmitters norepinephrine Some Trade Names
LEVOPHED
or serotonin, may be involved. (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 symptoms of bipolar disorder—depression and mania—can occur in certain disorders, such as high levels of thyroid hormone (hyperthyroidism). Also, episodes may be triggered by drugs, such as cocaine and amphetamines.

Some Causes of Mania

Condition

Examples

Brain and nervous system disorders

  • Brain tumors
  • Head injury
  • Huntington's disease
  • Multiple sclerosis
  • Seizures that affect the temporal lobe (complex partial seizures)
  • Stroke
  • Sydenham's disease

Connective tissue disorders

Systemic lupus erythematosus (lupus)

Infections

  • AIDS
  • Encephalitis
  • Influenza
  • Syphilis (late stage)

Hormonal disorders

High levels of thyroid hormones (hyperthyroidism)

Drugs

  • Amphetamines
  • Antidepressants (most)
  • Antidepressant withdrawal
  • Bromocriptine Some Trade Names
    PARLODEL
  • Cocaine
  • Corticosteroids
  • Levodopa Some Trade Names
    DOPAR
    LARODOPA
  • Methylphenidate Some Trade Names
    RITALIN
    CONCERTA
    METHYLIN

Symptoms

In bipolar disorder, episodes of symptoms alternate with virtually symptom-free periods (remissions). Episodes last anywhere from a few weeks to 3 to 6 mo. 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 with each cycle. In most, one or the other predominates to some extent.

Depression: Depression in bipolar disorder resembles depression that occurs alone (see Mood Disorders: Symptoms). People feel excessively sad and lose interest in their activities. They think and move slowly and may sleep more than usual. They may be overwhelmed with feelings of hopelessness and guilt.

Mania: 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 business endeavors, gambling, or dangerous sexual behavior) after another, without thinking about the consequences (such as loss of money or injury). However, people tend to 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 schizophrenia (see Schizophrenia and Delusional Disorder: 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; patients 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: 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. However, people in this mental state often make commitments that they cannot keep or start projects that they do not finish. They are easily distracted and easily irritated, sometimes resulting in angry outbursts. They rapidly change moods. People with hypomania 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. At least one of three people with bipolar disorder have mixed episodes.

Diagnosis

The diagnosis is based on the distinctive pattern of symptoms. 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. 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.

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

Treatment

For severe mania or depression, hospitalization is often required. For less severe mania, hospitalization may be needed during periods of overactivity to protect people and their family members from disastrous financial activities or sexual behavior. Most people with hypomania can be treated as outpatients. People with rapid recycling 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 Some Trade Names
LITHANE
LITHONATE
and some anticonvulsants), antipsychotic drugs, and certain antidepressants, as well as psychotherapy. Electroconvulsive therapy is sometimes used when mood stabilizers do not relieve depression. Phototherapy may be used when moods are related to the seasons.

Lithium: Lithium Some Trade Names
LITHANE
LITHONATE
can lessen the symptoms of mania and depression. Lithium Some Trade Names
LITHANE
LITHONATE
helps prevent mood swings in many people. Because lithium Some Trade Names
LITHANE
LITHONATE
takes 4 to 10 days to work, a drug that works more rapidly, such as an anticonvulsant or a newer (second-generation) antipsychotic drug, is often given to control excited thought and activity.

Lithium Some Trade Names
LITHANE
LITHONATE
can have side effects. It can cause 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 Some Trade Names
LITHANE
LITHONATE
must be stopped because of side effects, which then resolve. Doctors monitor the level of lithium Some Trade Names
LITHANE
LITHONATE
in the blood with regular blood tests because if levels are too high, side effects are more likely. Long-term use of lithium Some Trade Names
LITHANE
LITHONATE
can cause hypothyroidism and rarely can impair kidney function. Therefore, thyroid and kidney function must be monitored with regular blood tests.

A very high level of lithium Some Trade Names
LITHANE
LITHONATE
in the blood can cause persistent headaches, mental confusion, drowsiness, seizures, and abnormal heart rhythms. Side effects are more likely to occur in older people and people with impaired kidney function. Women who are trying to become pregnant must stop taking lithium Some Trade Names
LITHANE
LITHONATE
because rarely, lithium Some Trade Names
LITHANE
LITHONATE
can cause heart defects in a developing fetus.

Anticonvulsants: The anticonvulsants carbamazepine Some Trade Names
TEGRETOL
, oxcarbazepine Some Trade Names
TRILEPTAL
, and valproate Some Trade Names
DEPARENE
may be used to treat mania when it first occurs or to treat mania and depression when they occur together (mixed state). Unlike lithium Some Trade Names
LITHANE
LITHONATE
, these drugs do not damage the kidneys. However, carbamazepine Some Trade Names
TEGRETOL
can greatly reduce the number of red and white blood cells. Rarely, valproate Some Trade Names
DEPARENE
damages the liver (primarily in children) or severely damages the pancreas. With close monitoring by a doctor, these problems can be caught in time. Carbamazepine Some Trade Names
TEGRETOL
and valproate Some Trade Names
DEPARENE
can be useful, especially when people have not responded to other treatments. Oxcarbazepine Some Trade Names
TRILEPTAL
has fewer side effects.

Lamotrigine Some Trade Names
LAMICTAL
is sometimes used, especially during episodes of depression. Lamotrigine Some Trade Names
LAMICTAL
can cause a serious rash. Rarely, the rash becomes the life-threatening Stevens-Johnson syndrome (see Itching and Noninfectious Rashes: Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis). People who are taking lamotrigine Some Trade Names
LAMICTAL
should watch for any new rash or flu-like symptoms and report these symptoms to the doctor.

Antipsychotics: 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, olanzapine Some Trade Names
ZYPREXA
, quetiapine Some Trade Names
SEROQUEL
, risperidone Some Trade Names
RISPERDAL
, and ziprasidone Some Trade Names
GEODON
.

Long-term side effects may include weight gain and the metabolic syndrome. Metabolic syndrome (see Obesity 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 Some Trade Names
GEODON
.

Antidepressants: All antidepressants can cause swings from depression to hypomania or mania, sometimes rapidly. Therefore, these drugs are used only for short periods and usually are given along with a mood-stabilizing drug. Their effect on mood is closely monitored. At the first sign of a swing to hypomania or mania, the antidepressant is stopped.

Psychotherapy: 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: 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 Some Trade Names
NICORETTE
NICOTROL
) 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.

Last full review/revision June 2008 by Dwight L. Evans, MD

Back to Top

Previous: Introduction

Next: Cyclothymic Disorder

Audio
Figures
Photographs
Pronunciations
Tables
Videos
Contact UsSite MapAccessibility StatementPrivacy PolicyTerms of UseCopyright 1995-2009 Merck & Co., Inc.