Previously, the diagnostic criteria for both a manic and depressive episode had to be met in a consistent and sustained fashion, with symptoms enduring for at least a week (or any duration if psychiatric hospitalization was required), thereby restricting the official acknowledgement of mixed affective states to only a minority of patients with bipolar I disorder.

[2] A call was made by Tohen in 2017 for introducing changes from a currently phenomenological to a target oriented approach to DSM-5 mixed mood criteria in order to achieve more personalized medical attention.

People with emotional lability may seem to have suddenly developed anger issues or an anxiety disorder; they may seem to overreact in many or most situations; they may go from depressed to rapidly being "cured" or manic in just a few hours.

There also may be inappropriate and impulsive decision making, which can have severe, life changing, or even deadly consequences (like binge eating, excessive arguments, and an increased chance for suicide).

Even when such experiences are accounted for on the basis of depression, the possibility does still exist, however, that the depressive episode may be complicated by other manic or hypomanic symptoms, in which case it is often prudent to attend to the patient's personal and family history (e.g., family history of bipolar disorder, early age of onset) to determine whether or not the patient has bipolar disorder.