Bipolar disorder is a serious psychiatric disorder characterized by alternating episodes of depression, hypomania, mania, and mixed states. The disorder has a poor prognosis, with high rates of relapse, suicide and self-harm, and can impair a variety of behaviors and functions, placing a heavy burden on the patient and his or her family. Bipolar disorder depressive episodes and monophasic depression are two different disorders with different pathogenesis, but early clinical distinction is difficult. Firstly, 3/4 (female) or 2/3 (male) of bipolar disorder start with depressive episodes, which can be easily misdiagnosed as monophasic depression; secondly, the early identification of bipolar disorder currently relies mainly on clinical features, while most clinical features have no absolute boundaries in the two disorders and are characterized by variability and uncertainty, and lack specific biological indicators for early identification of bipolar disorder. Approximately 40% of patients with bipolar disorder have been misdiagnosed as monophasic depression, with an average misdiagnosis time of up to 7.5 years, and about 1/3 of patients with bipolar disorder have their outcome compromised by failure to use mood stabilizers. Therefore, early identification and appropriate treatment are important for the prognosis of patients with bipolar disorder. Xuzhou Psychiatric Hospital Psychiatric Department You Jiayong Classical classification and prevalence 1. Bipolar I disorder: Bipolar disorder with both manic (not only light manic) episodes and major depressive episodes. If the manic episode is caused by antidepressants or other drugs, the diagnosis cannot be made yet. Lifetime prevalence: 0.4%-1.6%. 2, bipolar II disorder: bipolar disorder with mild manic episodes but no manic episodes. the diagnosis of mild manic symptoms in DSM-IV-TR is relaxed, and the duration of episodes can be less than 4 days, such as lasting 2-3 days. Lifetime prevalence: about 0.5%. 3. Rapid cyclic bipolar disorder: ICD-10 criteria: A. Must meet the criteria for bipolar disorder; B. Must have at least four episodes of bipolar disorder within a 12-month period. Rapid cyclic episodes are commonly seen in bipolar II and are more common in women. Lifetime prevalence: 5-10% of patients with bipolar disorder. 4.Mixed state of bipolar disorder: ICD-10 criteria: mania, hypomania and depression must be prominent at the same time or mania and depression must alternate rapidly within a few hours for most of the time in at least 2 weeks; DSM-IV has a stricter definition of mixed state, and only those who meet the diagnostic criteria of manic episode and major depressive episode at the same time and last for at least one week are diagnosed as mixed state. Lifetime prevalence: about 30-40% of bipolar disorder. Some scholars put forward the concept of “soft bipolar”. Soft bipolar refers to the current depressive episode, and indeed no manic or hypomanic episodes in the past, but has certain characteristics of depressive disorder, these characteristics can predict the future manic or hypomanic episodes, can be said to be “depression” into the transition concept of bipolar disorder, also known as “pseudo-monophasic It is also known as “pseudo-monophilia”. Existing research suggests that soft bipolar has many risk factors, such as female, early age of onset (usually before 25 years old, or even in the late teens), energetic temperament, cyclothymic temperament and borderline personality disorder, family history of bipolar disorder, suicide, borderline personality disorder, more frequent episodes, more pronounced biological rhythm such as morning heavy and night light, depressive episodes with mixed, atypical or The depressive episodes are mixed, atypical or agitated, etc. Treatment of bipolar disorder Bipolar I acute mania or bipolar II light manic episodes can be preferred to lithium. If the previous efficacy of lithium salts is poor you can choose valproate or carbamazepine, or add valproate or carbamazepine on top of lithium salts. For rapid cycling episodes or mixed episodes, valproate or carbamazepine or a combination with other mood stabilizers is preferred. The newer antipsychotics risperidone, quetiapine and olanzapine are all effective for mixed episodes, but olanzapine is currently the more studied. The treatment of bipolar depression can be preferred to lithium or lamotrigine, and more severe depression can be treated with antidepressants on top of lithium. 11.2% of TCAs, 3.7% of SSRIs and 4.2% of placebos are used, so try to use antidepressants with a small rate of mania. For refractory cases, lithium and valproate or carbamazepine can be combined, and if they are ineffective, another mood stabilizer can be considered, or a second-generation antipsychotic can be added.