According to the DSM-IV-TR, a hypomanic episode includes, over the course of at least 4 days, elevated mood plus three of the following symptoms OR irritable mood plus four of the following symptoms:
In the hypomanic state, people may feel like they can't slow their mind down, and that all these speeding thoughts are amazingly perfectly crafted. Some examples are speaking or writing in rhyme or alliteration without planning it first; quick responses to people talking; or the ability to improvise easily on the spot.
Another type of behavioral response sometimes included as a symptom is emotional flattening or blunted affect. A person may seem unusually cold, uncaring, or arrogant, showing little or no emotional responsiveness.
The less severe form of high in bipolar disorder is hypomania. People with this form have increased energy and tend to become more active than usual. They do not, however, have delusions or hallucinations. They do not lose touch with reality in the sense that they know who they are and what is real. What can be a problem, however, is that they tend to overestimate their capabilities and fail to see the obvious risks involved in their ventures. For example, if they are in business, they may suddenly decide to expand in a way that is not really practical or set up schemes for which they are ill prepared. Other forms of less inhibited behavior include reckless driving, gambling, spending sprees and sexual adventures. They may also have lots of new ideas but do not follow them through. They are often very jolly to be with but can quickly become very impatient or unpleasant if they cannot get what they want.
When a patient presents with a history of one or more hypomanic episodes and one or more depressive episodes that meet the criteria for a Major Depressive Episode, Bipolar II Disorder is diagnosed.
If left untreated, hypomania can slip deeper and deeper into mania (and sometimes psychosis), in which case, Bipolar I Disorder is often diagnosed. (See also, Kindling model)
It is unknown to what degree hypomanic symptoms can occur without a depressive component. Patients may be relatively unlikely to seek psychiatric treatment for hypomania alone. However, many hypomanic patients experience:
Plus other out-of-character behaviors that the person may regret following the conclusion of the mood episode.
Hypomania can signal the beginning of a more severe manic episode, and often does result in a more severe manic episode if the hypomanic episode remains untreated. A hypomanic episode can also directly precede a depressive episode.
Virtually all clinical trials of medications for the non-depressive phases of bipolar illnesses involve treating patients for psychotic mania during the initial, or acute, phase of mania. Such trials are the basis upon which appropriate medication is recommended; high doses are justified in the case of mania, in order to remove the patient from immediate danger. This is in direct contrast to hypomania, however, which involves different considerations and almost always demands much greater case-by-case clinical judgment. Typical prescribed medications for hypomania include mood stabilizers such as Depakote and lithium carbonate as well as atypical antipsychotics such as Zyprexa and Seroquel.
Radiohead front man Thom Yorke reportedly responded, "Hypomania? Yes, that's exactly what it was," when asked about his mental state after the release of the group's classic album OK Computer. Iggy Pop was diagnosed with hypomania during his stay in a mental hospital in the mid 1970's. It has also been suggested that Richey Edwards, the "fatalistic Manic Street Preacher" (Mojo magazine, 2003) and the late Syd Barrett of the band Pink Floyd have experienced hypomania. In the biographical documentary An Unreasonable Man. Honoré de Balzac, French author of the Human Comedy, is attributed with having hypomania; his writing sessions continued from midnight to noon, functioning on four hours of sleep. Intermittently during these episodes, Balzac would consume massive amounts of coffee. However, it is far from apparent whether these are based on psychiatric diagnosis: bipolar symptoms are frequently misunderstood, misattributed and glamorized in popular culture.
John Gartner's unverified book The Hypomanic Edge claims notable people including Christopher Columbus, Alexander Hamilton, Andrew Carnegie, Howard Zinn and Louis B. Mayer owe their innovativeness and drive, as well as their eccentricities, to hypomanic temperaments. Critics, however, assert that Gartner vastly overstates his case. Within the book, Gartner points out that the constructive behaviors associated with hypomania may contribute to bipolar disorder's evolutionary survival; he fails, however, to address the possibility that the depressive component may be the evolutionary adaptive mechanism instead, a theory which has been postulated by various evolutionary psychologists.