Diagnostic Criteria and Assessment for Bipolar II Disorder

Core Diagnostic Requirements

The American Psychiatric Association recommends that Bipolar II disorder requires at least one major depressive episode AND at least one hypomanic episode, with no history of full manic episodes 1

The assessment of past psychiatric diagnoses and any prior misdiagnoses, particularly unipolar depression, is critical 2
A thorough antidepressant response history is necessary, as antidepressant-induced mood elevation or agitation strongly suggests underlying bipolarity, with approximately 20% of youths with major depression eventually developing manic episodes 2, 3
Family psychiatric history, particularly of mood disorders, is important, as first-degree relatives have a 4-6 fold increased risk 2
Substance use history with toxicology screening is necessary to rule out substance-induced mood disorder 2

Mixed features, such as depressive symptoms with concurrent subsyndromal hypomanic symptoms like racing thoughts or increased energy, are common and should raise suspicion for bipolarity 2
The key distinction between Bipolar I and Bipolar II centers on severity, with hypomania often increasing functioning, whereas mania causes marked impairment requiring hospitalization 2

Assessing suicidality thoroughly is necessary, as Bipolar II has suicide completion rates at least equivalent to Bipolar I disorder 2
Screening for anxiety disorders and substance use disorders is important, as they are highly comorbid 2
Evaluating for ADHD, PTSD, and disruptive behavior disorders is necessary, as manic symptoms must be differentiated from these conditions 2, 1

A complete medical workup, including thyroid function tests, complete blood count, and comprehensive metabolic panel, is necessary to exclude organic causes 2
Vital signs and neurologic examination are necessary to identify medical conditions causing or exacerbating symptoms 2

Quetiapine or lamotrigine are first-line treatments for bipolar depression 3
Lithium has strong long-term evidence and is FDA-approved for bipolar disorder maintenance, reducing frequency and intensity of episodes 3
Valproate is FDA-approved for acute mania and can be used as initial therapy 3
Antidepressant monotherapy is contraindicated in bipolar depression, and if antidepressants are necessary for severe depression, they must be combined with a mood stabilizer 3
Psychoeducation about symptoms, course, treatment options, impact on functioning, and heritability is necessary 1
Relapse prevention education focusing on medication compliance, recognition of emergent symptoms, and factors precipitating relapse is important 1
Family-focused therapy and interpersonal/social rhythm therapy have demonstrated benefit 1