This article is from the Bipolar Disorder FAQ, by barry@webveranda.com (Barry Campbell) with numerous contributions by others.
Bipolar Disorder is the medical name for Manic Depression; at various times, it
has also been known as Bipolar Affective Disorder and Manic-Depressive Illness.
It is a mood disorder that affects approximately 1% of the adult population of
the United States--and roughly the same percentage in other countries, as far
as we know. :-)
It's in the same family of illnesses (called "affective disorders") as clinical
depression. However, unlike clinical depression, which seems to affect far more
women than men, Bipolar Disorder seems to affect men and women in approximately
equal numbers.
It's characterized by mood swings. Though there is no known cure, most forms
of bipolar disorder are eminently treatable with medication and supportive
psychotherapy.
The textbook definition of Bipolar Disorder is: one or more Manic or Hypomanic
Episodes, accompanied by one or more Major Depressive Episodes. These episodes
typically happen in cycles.
All of these terms will be defined at greater length below...but in plain
English, a person who has Bipolar Disorder will be severely up some of the
time, severely down some of the time, and in the middle some or most of the
time.
There are two main types of Bipolar Disorder:
-- Bipolar I is the "classic" form of Bipolar Disorder. It most often involves
widely spaced, long-lasting bouts of mania followed by long-lasting bouts of
depression and vice-versa. However, the essential definition is depression
plus mania, or "mixed states."
-- Bipolar II involves at least one Hypomanic Episode and one Major Depressive
Episode, but never either a full-blown Manic Episode or Cyclothymia. The
essential definition is depression plus hypomania.
Although the shifts from one state to another are usually gradual, they can be
quite sudden. The "rapid-cycling" form of the disorder involves four or more
complete mood cycles within a year's time, and some rapid-cyclers can complete
a mood cycle in a matter of days--or, more rarely, in hours.
It is also possible for someone who has Bipolar Disorder to be in a "mixed
state." This means that they're in a mood state which has some characteristics
of depression and some of mania or hypomania.
There are a few rare documented cases of mania without depression, but DSM-IV
does not currently include a category for just "mania". (This diagnosis was
present in DSM-III, but is unaccountably absent in DSM-IV!)
Using DSM-IV, a person exhibiting the symptoms of mania will almost always be
diagnosed as bipolar. The general feeling in the mental health community seems
to be that what or whom goes up, must eventually come down.
The DSM-IV and "extended" definitions of depression and mania are presented in
the sections that follow. It is very important to remember the following:
-- These definitions are not a guide for self-diagnosis!
-- One does not need to exhibit *all* of the symptoms of depression to be
depressed, nor does one need to display *all* of the symptoms of mania to be
manic.
 
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