There are several types of bipolar disorder; all involve episodes of depression and mania to a degree.
Bipolar disorder is a lifelong illness. Episodes of mania and depression eventually can occur again, if you don't get treatment. Many people sometimes continue to have symptoms, even after getting treatment for their bipolar disorder. Here are the types of bipolar disorder:
Bipolar Idisorder involves periods of severe mood episodes from mania to depression.
Bipolar IIdisorder is a milder form of mood elevation, involving milder episodes of hypomania that alternate with periods of severe depression.
Cyclothymic disorder describes periods of hypomania with brief periods of depression that are not as extensive or long-lasting as seen in full depressive episodes.
Mixed bipolar episodes are periods that simultaneously involve the full symptoms of both a manic and a full depressive episode. It's marked by grandiose feelings with racing thoughts. At the same time, the person is irritable, angry, moody, and feeling bad.
Rapid-cycling bipolar disorder is characterized by four or more mood episodes that occur within a 12-month period. Episodes must last for some minimum number of days in order to be considered distinct episodes. Some people also experience changes in polarity from high to low or vice-versa within a single week, or even within a single day -- the full symptom profile that defines distinct, separate episodes may not be present (for example, the person may not have a decreased need for sleep), making such "ultra-rapid" cycling a more controversial phenomenon. Rapid cycling can occur at any time in the course of illness, although some researchers believe that it may be more common at later points in the lifetime duration of illness. Women appear more likely than men to have rapid cycling. A rapid-cycling pattern increases risk for severe depression and suicide attempts. Antidepressants are thought to trigger and prolong rapid cycling in bipolar disorder. However, that theory is controversial and is still being studied.