There are a number of kinds and complexities of mood episodes, so the Diagnostic and Statistical Manual of Mental Disorders (a book that emphasizes mental health diagnoses) has classified the diagnosis of bipolar disorder into four basic categories. Each category is defined by a particular set of routine of spontaneous depressions, manias, hypomanias or mixed episodes.
Classification of Bipolar Disorder
Bi polar I Disorder is applicable to individuals who have manic and depressive episodes. Bipolar II Disorder is applicable to individuals who have depression but only hypomanic presentations; no true manias are involved. Cyclothymic Disorder is applicable to individuals who have repeated mood swings that are never quite complex enough to qualify as major depressive or manic episodes. Bipolar Disorder Not Otherwise Specified (NOS) is applicable to individuals who do not fit into the other categories.
The prominent issue in bipolar mood swings has to do with their periodicity (how long each episode lasts and how fast they fluctuate). The majority of times, bipolar mood swings make their presence felt with relative slowness, over periods of weeks and months. In an ideal scenario, less than four complete mood cycles happen within a given year and each mood episode can last up to two months.
There is usually a period of relatively normal mood that arises between mood episodes. Some individuals do not experience this normal inter-episode period. Instead they experience this gap at a point in time when their mood symptoms are in a controlled frame of mind rather than a typical normal mood.
Fast cycling bipolar disorder is easily identified, though it is less common. Fast cycling bipolar disorder means mood cycle periods occur four or more times per year. Recent researches have shown that fast cycling bipolar conditions occur in around 20% bipolar patients.
Ultra Fast and Ultridian Cycling
There is some speculation that two more cycling terms will be introduced very soon. The first is Ultra-fast cycling which will be used in cases where entire mood cycles occur in less than one month. Ultridian cycling will be used to signify cases where entire mood cycles occur inside the space of one day. Fast cycling in any kind of bipolar disorder tends to be linked with a poor long-term prognosis. Fast cyclers do not tend to hold their lives together as well as bipolar patients with longer cycles.
There are other conditions which can lead to mood swings. Mood swings can be caused by general medical conditions or other physical illnesses that affect the body's regulatory systems. Suspected medical conditions consist of brain chemical imbalances, hormone disorders, bacterial or viral infections and autoimmunity conditions. Experts believe that such illnesses can cause people to experience bipolar-like mood swings even though they are not suffering from actual bipolar disorder.
More confusing is the use of illicit drugs and/or alcohol, which can give rise to modified mood states. A stimulant drug, like Cocaine, can easily mimic a manic state as it affects the central nervous system. A depressant drug, like alcohol, can easily mimic a depressive state. When the health care provider is not sure about the mood, they can hold off making definitive diagnoses until enough time has passed to allow any drug that might have some effect on the mood to metabolize. As manic people tend to demonstrate poor judgment, it is not at all uncommon for them to take drugs and/or alcohol. People experiencing a depressive episode tend to feel awful and will "self-medicate" with street drugs and/or alcohol in an effort to feel better.