Mood Disorders

This short article provides an overview of several mood disorders, while more detailed information about each specific mood disorder is available in the rest of this section.

How much of the population is affected by mood disorders?

Each year, almost 44 million Americans experience a mental disorder. In fact, mental illnesses are among the most common conditions affecting health today.

What causes mood disorders / mental illness?

Researchers believe most serious mental illnesses are caused by complex imbalances in the brain’s chemical activity. They also believe environmental factors can play a part in triggering, or cushioning against, the onset of mental illness.

Are mood disorders treatable?

Like other diseases, mental illnesses can be treated. The good news is that most people who have mental illnesses, even serious ones, can lead productive lives with proper treatment. Mood disorders are one form of serious mental illness.

What are some common mood disorders?

Two of the most common mood disorders are depression and bipolar disorder, also known as manic-depressive illness.

Bipolar Disorder


Extreme mood swings punctuated by periods of generally even-keeled behavior characterize this disorder. Bipolar disorder tends to run in families. This disorder typically begins in the mid-twenties and continues throughout life. Without treatment, people who have bipolar disorder often go through devastating life events such as marital breakups, job loss, substance abuse, and suicide.


Mania-expansive or irritable mood, inflated self-esteem, decreased need for sleep; increased energy; racing thoughts; feelings of invulnerability; poor judgment; heightened sex drive; and denial that anything is wrong. Depression-feelings of hopelessness, guilt, worthlessness, or melancholy; fatigue; loss of appetite for food or sex; sleep disturbances, thoughts of death or suicide; and suicide attempts. Mania and depression may vary in both duration and degree of intensity.

Formal Diagnosis

Although scientific evidence indicates bipolar disorder is caused by chemical imbalances in the brain, no lab test exists to diagnose the disorder. In fact, this mental illness often goes unrecognized by the person who has it, relatives, friends, or even physicians. The first step of diagnosis is to receive a complete medical evaluation to rule out any other mental or physical disorders. Anyone who has this mental illness should be under the care of a psychiatrist skilled in the diagnosis and treatment of bipolar disorder.


Eighty to ninety percent of people who have bipolar disorder can be treated effectively with medication and psychotherapy. Self-help groups can offer emotional support and assistance in recognizing signs of relapse to avert a full-blown episode of bipolar disorder. The most commonly prescribed medications to treat bipolar disorder are three mood stabilizers: lithium carbonate, carbamazepine, and valproate.



When a person’s feelings of sadness persist beyond a few weeks, he or she may have depression. According to the National Institute for Mental Health, three to four million men are affected by depression; it affects twice as many women. Researchers do not know the exact mechanisms that trigger depression. Two neurotransmitters-natural substances that allow brain cells to communicate with one another-are implicated in depression: serotonin and norepinephrine.


Changes in appetite and sleeping patterns; feelings of worthlessness, hopelessness, and inappropriate guilt; loss of interest or pleasure in formerly important activities; fatigue; inability to concentrate; overwhelming sadness; disturbed thinking; physical symptoms such as headaches or stomachaches; and suicidal thoughts or behaviors.

Formal Diagnosis

Four or more of the previous symptoms have been present continually, or most of the time, for more than 2 weeks. The term clinical depression merely means the episode of depression is serious enough to require treatment. Major depression is marked by far more severe symptoms, such as literally being unable to drag oneself out of bed. Another form of depression, known as seasonal affective disorder, is associated with seasonal changes in the amount of available daylight.


Some types of cognitive/behavioral therapy and interpersonal therapy may be as effective as medications for some people who have depression. Special bright light helps many people who have seasonal affective disorder.

Three major types of medication are used to treat depression: tricyclics; the newer selective serotonin re-uptake inhibitors (SSRIs), and monoamine oxidase inhibitors (MAO inhibitors). Electroconvulsive therapy uses small amounts of electricity applied to the scalp to affect neurotransmitters in the brain. Usually referred to as ECT, this highly controversial and potentially life-saving technique is considered only when other therapies have failed, when a person is seriously medically ill and/or unable to take medication, or when a person is very likely to commit suicide. Substantial improvements in the equipment, dosing guidelines and anesthesia have significantly reduced the possibility of side effects.

For more information and referrals to specialists and self-help groups in your State, contact:

Depression and Bipolar Support Alliance (DBSA)
(formerly the National Depressive and Manic-Depressive Association)
730 N. Franklin Street, Suite 501
Telephone: 800-826-3632
Fax: 312-642-7243

National Foundation for Depressive Illness
P.O. Box 2257
New York, NY 10016
Telephone: 800-239-1265

Note: These are suggested resources. It is not meant to be a complete list.

This article appears courtesy of the US government’s National Mental Health Information Center.

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