Bipolar disorder is a condition that causes extreme shifts in mood, energy, and functioning. In most populations it affects around 1 percent of the population. Men and women are equally likely to develop this often-disabling illness. The disorder typically emerges in adolescence or early adulthood and affects sufferers throughout their lifespan. Although traditionally thought of as an adult disorder, there is now recognition that children also suffer from bipolar disorder. There are no definite known causes. Scientists believe that Bipolar Disorder may be caused by a combination of biological and psychological factors. Most commonly this disorder can be linked to stressful life events. Cycles, or episodes, of depression, mania, or "mixed" manic and depressive symptoms typically recur and may become more frequent, often disrupting work, school, family, and social life. The Kindling theory suggests that persons who are genetically prone (toward bipolar) experience a series of stressful events, each of which lowers the threshold at which mood changes occur. Then at some point these mood changes occur spontaneously. The person then "becomes bipolar". This might explain why the cause of bipolar is difficult to pinpoint but is somehow related to genetics and environment.

There is a tendency to romanticize bipolar disorder, especially in artistic circles. Many artists, musicians, and writers have experienced its mood swings, and some credit the condition with their creativity. However, many lives are ruined by this disease, and it is associated with a greatly increased risk of suicide.

Bipolar disorder manifests itself in numerous ways, most notably:

  1. Depression: Symptoms include a persistent sad mood; loss of interest or pleasure in activities that were once enjoyed; significant change in appetite or body weight; difficulty sleeping or oversleeping; physical slowing or agitation; loss of energy; feelings of worthlessness or inappropriate guilt; difficulty thinking or concentrating; recurrent thoughts of death or suicide.
  2. Mania: Abnormally and persistently elevated (high) mood and/or irritability accompanied by at least three of the following symptoms (four if the mood is merely irritable): overly-inflated self-esteem; decreased need for sleep; increased talkativeness; racing thoughts; distractibility; increased goal-directed activity such as shopping; physical agitation; hypersexuality; excessive involvement in risky behaviors or activities. There is a less severe form of mania that may also be present -- hypomania
  3. Mixed state: Symptoms of mania and depression are present at the same time. The symptom picture frequently includes agitation, trouble sleeping, significant change in appetite, psychosis, and suicidal thinking. Depressed mood accompanies manic activation. Also known as dysphoric mania (from Greek 'dysphoria', 'dys', difficulty, 'phorós', bearer, and 'mania', mania, insanity). This is the form most often seen in children.

Especially early in the course of illness, the episodes may be separated by periods of wellness during which a person suffers few to no symptoms. When four or more episodes of illness occur within a 12-month period, the person is said to have bipolar disorder with rapid cycling. The rapid-cycling form is often considered more difficult to treat and may be more disabling for bipolar persons since the mood transitions are faster. Bipolar disorder is often complicated by co-occurring alcohol or substance abuse.

Severe depression or mania may be accompanied by symptoms of psychosis. These symptoms include: hallucinations (hearing, seeing, or otherwise sensing the presence of stimuli that are not there) and delusions (false personal beliefs that are not subject to reason or contradictory evidence and are not explained by a person's cultural concepts). Psychotic symptoms associated with bipolar disorder typically reflect the extreme mood state at the time. Mania is associated with unwarranted optimism, and depression with unwarranted pessimism.