Bipolar disorder manifests itself in numerous ways, most notably:
Depression: symptoms include a persistent sad mood; loss of interest or pleasure in activities that were once enjoyed; significant changes in body weight; significant changes in appetite; difficulty sleeping or oversleeping; physical slowing or agitation; loss of energy; feelings of worthlessness or inappropriate guilt; difficulty thinking or concentrating; recurrent thoughts of self-harm, death or suicide. (Some people are also diagnosed and treated for obsessive compulsive disorder, anxiety, and/or panic disorder.)
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 or unusual behaviors or activities. Mania is often divided diagnostically into two categories:
full-blown manic episodes, and
hypomania, a less severe form of mania.
Hypomania is often not especially problematic for the patient, as he or she typically feels very energetic and in a very good mood. As such, hypomania is often unreported and undiagnosed (this is perhaps the biggest cause of incorrect diagnoses between unipolar and bipolar depression.) Some patients experience only hypomania; in others, hypomania progresses into a full manic state in which the patient has more and more trouble retaining control, and the symptoms become more problematic. For some people, hypomania is an acceptable baseline.
Hypomania and mania can both make a person angry, making the mood shift harder to detect as even government guidelines advise that you watch for euphoria. Some people with bipolar disorder will never have full-blown mania; while others will have it rarely.
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 negative thinking, some of which may be automatic (see Automatic Negative Thought (ANT) ). In a mixed state, depressed mood accompanies manic "activation". Also known as dysphoric mania (from Greek dysphoria: dys, difficulty, phorós, bearer); it does not euphoric characteristics. This is the form most often seen in children.
Bipolar disorder takes two principle forms, neither of which requires plural "cycles". According to the DSM-IV-TR (p. 345), these two principal forms of Bipolar disorder are:
Bipolar I disorder, the diagnosis of which requires over the entire course of the individual's life at least one manic (or mixed) state episode which is usually (though not always) accompanied by major depressive episodes.
Bipolar II disorder, which over the course of the individual's life must involve at least one major Depressive episode and must be accompanied by at least one hypomanic episode. There must be no manic episodes. If there were manic episodes, the accurate diagnosis would be Bipolar I.
Therefore, bipolar disorder need not have both severe manic episodes and depressive episodes. In certain cases the sufferer has only episodes of mania. There need be no "cycles" of mania and depression.
This is why certain contemporary psychiatrists avoid from the original name, "manic depression", which suggests that all individuals have both mania and depression. It is unrelated with the notion of equal distribution of cycles of mania and depression, since there need not be any cycles at all—in fact, even when there is one (or more) bout of both mania and depression over the course of an individual's life, the two episodes may be so unrelated to each other temporally and otherwise that this need not constitute a cycle. However, a significant portion of individuals with bipolar experience the classical alternating episodes (cycles) of mania and depression and therefore it is overstating the case to say that the classical alternation "rarely" occurs.
The DSM-IV treats these bipolar disorders as variants of mood disorders (or affective disorders). Other types include major depressive disorder and dysthymic disorder. Bipolar and other mood disorders may have no identifiable medical, traumatic or other external cause (exogenous) or may be due to a medical condition (endogenous). Current psychiatric view no longer labels mood episodes as endogenous or exogenous. The exceptions being a substance induced mood disorder or a mood disorder due to a general medical condition.
In order for a person to be properly diagnosed with bipolar disorders, the mood episodes cannot be due to external medication, drugs or treatment for depression.
Emil Kraepelin included in his original description of manic depression the phenomenon that episodes of acute illness, whether mania or depression, are usually punctuated by relatively symptom-free intervals during which the patient is able to function normally both at work and in social affairs.
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 episodes typically include euphoria, tirelessness, and impulsiveness; the depressed periods may seem much worse following a manic period.
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.