Bipolar disorder type 2 is the type of symptom that has had a previous mild manic episode and also a depressive episode. Bipolar disorder is a more serious mental illness, especially when there will be a mild manic manifestation, the patient may have some self-awareness, but can not fully self-control their own behavior, sometimes there will be emotional high, excitement, social function is mildly impaired, but in general it is not easy for ordinary people to notice. As for depression, typical symptoms are depressed mood, unhappiness, slowed thinking, decreased concentration, decreased memory, and possibly decreased volitional activity, such as reluctance to see people, reluctance to go out, and so on. It may also be accompanied by somatic symptoms, such as various physical discomforts, fatigue, loss of appetite, and sleep disturbances, especially insomnia. If bipolar disorder type 2 has been identified, treatment must be actively pursued, especially considering taking mood stabilizers, such as lithium carbonate and valproate, for treatment and intervention.