The cycles of bipolar disorder may be long or short, and the ups and downs may be of different magnitudes: for instance, a person suffering from bipolar disorder may suffer a protracted mild depression followed by a shorter and intense mania. The manic periods typically include euphoria, tirelessness, and impulsiveness; the depressed periods may seem much worse following a manic period.
The name bipolar disorder is used to distinguish the condition from unipolar depression, and bipolar disorder is in turn divided into two forms, [Bipolar I]? and the "milder" [Bipolar II]? form.
Medications, called "mood stabilizers" can be used to prevent manic or depressive episodes. (See http://people.ne.mediaone.net/pmbrig/BP_pharm.html for a summary of the psychopharmacology of bipolar disorder.) Periods of depression can also be treated with antidepressants. In extreme cases where the mania or the depression is severe enough to cause psychosis, antipsychotic drugs may also be used.
Compliance with medications can be a major problem because people becoming manic lose insight, or an awareness of having an illness, and discontinue medications; then they often suffer a manic episode and may suddenly find themselves initiating multiple projects often being scattered and ineffective, or may go on a spending spree or take a poorly planned trip landing them in an unfamiliar location without cash. The manic periods, euphoric as they may be, are often disastrous because of the impulsiveness and irrationality that comes with them. Contrary to the patient's wishes, the depression does not respond instantaneously to resumed medication, typically taking 2-6 weeks to respond.
Bipolar disorder appears to run in families, that is, a vulnerablility for bipolar disorder may be genetically inherited. The rate of suicide is higher in people who have bipolar disorder than in the general population. The rate of prevalence of bipolar disorder is roughly equal (around 1%) in men and women.
Whilst bipolar disorder can be one of the most severe and devastating medical conditions, many individuals with bipolar disorder can also live full and mostly happy lives with correct management of their condition. Unlike patients with schizophrenia, persons with bipolar disorder have periods of normal functioning between the extremes of mood.
The classic work on this subject is "Manic-Depressive Illness" by Frederick K. Goodwin and Kay Redfield Jamison. ISBN 0195039343 (amazon.com, search)
Many famous people have been affected by bipolar disorder, including Spike Milligan, Lord Byron and Winston Churchill. There appears to be an association between bipolar disorder and talent in many cases - this is documented in Jamison's book "Touched with Fire".
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