Bipolar II disorder differs from Bipolar I in that II does not have manic states. Hence, Bipolar I is now largely the domain of manic depression with delusions. Delusions are also not a part of Bipolar II disorder. There are a few new means to identify Bipolar II, and these lie in the nature of the depressive episodes.

Hypomania

Learn to identify "hypomania," literally, "beneath mania." Similar, but not as severe. This can be confusing. The basic symptoms of hyopmania are very good mood, rapid speech, racing thoughts, high energy and overconfidence. None of these are manic states, and delusions are not found in this list. Hence, diagnosing Bipolar II has more to do with what it does not have than what it does.

Nature of Bipolar II

Simply see Bipolar II disorder as containing swings from the hyopmanic phases to severe depression. The nature of Bipolar II depression is the key to distinguishing it from the more commonly diagnosed Bipolar I.

Depression

The nature of the depression in Bipolar II is nuanced. Its basic characteristics are depressive states, non-manic mixed with severe anxiety, irritability and insomnia, possibly in combination. Bipolar II depressive states also can be identified by the fact that it normally does not respond to anti-depressants.

"Soft Signs"

"Soft signs" are symptoms that do not necessarily point to a disease, but can confirm an already existing diagnosis. If the above symptoms are found, the following symptoms might confirm Bipolar II. These include repeated states of depression, genetic traits (relatives who have the disease), brief states of depression, loss of response to anti-depressants or even agitation as a result of taking anti-depressants. These might be pointers to Bipolar II, but they only confirm a diagnosis and should not be taken as directly symptomatic.

Source:

Identifying Bipolar II, Jim Phelps, MD