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Bipolar disorder

Last updated: April 7, 2021

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Bipolar disorder is a psychiatric illness characterized by episodes of mania (or hypomania) and major depression, interspersed with periods of normal mood and functioning. Men and women are equally affected, and there is a strong genetic component to the disease. During manic episodes, patients may experience elevated mood, talkativeness, racing thoughts, and psychosis, and often endanger themselves or others. Depressive episodes are characterized by sadness, anhedonia, and hopelessness. Although episodes of mania or depression can occur anytime, they are especially triggered by environmental factors (eg, lack of sleep, psychosocial stress). Manic episodes are treated acutely with lithium, antipsychotics, and benzodiazepines. Lithium is also commonly used for long-term treatment, as is valproic acid.

  • Sex: = [1]
  • Age of onset [2]
    • The average age of onset is 20 years
    • The frequency of depressive and manic episodes increases with age.
  • Lifetime prevalence
    • General population: 1–3%
    • First-degree relative with bipolar disorder: up to 10%
    • Monozygotic twin: 40–70%

Patients with bipolar disorder have a very high risk of suicide!

Epidemiological data refers to the US, unless otherwise specified.

  • Multifactorial origin
    • Strong genetic componentincreased risk if first-degree relative is affected (see “Epidemiology” above)
    • ↑ Paternal age → ↑ mutations during spermatogenesis ↑ risk of bipolar disorder in offspring
  • Triggers [2]
    • Childhood traumatic experiences
    • Psychosocial stress
    • Sleep disturbances
    • Physical illness

Features of a manic episode, hypomanic episode, or a major depressive episode interspersed with periods of normal mood and functioning

Features of manic and hypomanic episodes [3][4][5]

Diagnostic criteria according to DSM-V
Manic episode Hypomanic episode
Core definition
  • Abnormally elevated, expansive, or irritable mood and increased goal-directed behavior not attributable to an organic psychic disorder or psychotropic substances
  • Most of the day for at least 1 week
  • Most of the day for at least 4 consecutive days
  • ≥ 3 of the following:
    • Increased goal-directed activity (sexually, at work, and/or socially ) or psychomotor agitation
    • Increased talkativeness or pressure of speech
    • Flight of ideas or racing thoughts
    • Loss of social inhibitions
      • Hedonistic, socially inappropriate, and reckless behavior
      • Aggressiveness, hostility
    • Decreased need for sleep
    • Heightened self-esteem or grandiosity
    • Distractibility
Extent of dysfunction
  • Significant dysfunction (work/school), patient requires hospitalization (risk of harm to self or others), or presence of psychotic features
  • Does not result in significant dysfunction, hospitalization, or manifests with psychotic features

The main difference between mania and hypomania is the intensity of the symptoms. Symptoms of mania are much more intense than those of hypomania, result in significant dysfunction, and manic patients often require hospitalization. If psychotic symptoms are present, the episode is, by definition, manic and not hypomanic.

To remember the features of a manic episode, think: “DIG FAST” (Distractibility, Irresponsibility, Grandiosity, Flight of ideas, Activity increase, Sleep deficit, Talkativeness).

Major depressive episode [3][4][5]

Diagnostic criteria according to DSM-V
  • Clinically significant distress or impaired functioning in important areas of life (e.g., work, school)
  • Not due to effects of psychoactive substances or organic disease

In some patients, the initial diagnosis may be a recurrent depressive disorder, as depressive symptoms might be the only symptoms for several years.

To remember the features of major depressive episode, think: “SIG E CAPS” (Sleep (insomnia or hypersomnia), Interest loss (anhedonia), Guilt (low self-esteem), Energy (low energy or fatigue), Concentration (poor concentration or difficulty making decisions), Appetite (decreased appetite or overeating), Psychomotor agitation or retardation, and Suicidality).

Types of bipolar disorder [3][6]

  • Bipolar I disorder: at least one episode of mania. Major depressive or hypomanic episodes usually occur but are not required for diagnosis.
  • Bipolar II disorder: at least one episode of hypomania and one major depressive episode; no previous episodes of mania (distinguishing feature from bipolar I)

In contrast to bipolar II disorder, a history of major depressive episodes is not required for the diagnosis of bipolar I disorder.

Rapid cycling [3][6]

Cyclothymia [3][6]

  • Persistent instability of mood involving numerous periods of depression and periods of hypomania
  • Symptoms are not sufficiently severe or persistent enough to diagnose bipolar disorder.
  • Symptoms last at least 2 years, are present at least half of the time, and are never absent for more than 2 months at a time.

Substance/medication-induced bipolar and related disorder [3][6]

Always do a urine drug screening in patients presenting with mania.

  • Screening: structured questionnaires (e.g., the Mood Disorder Questionnaire for manic episodes and Patient Health Questionnaire-9 (PHQ-9) for depressive episodes)
  • Clinical diagnosis: See “Clinical features” above.

All patients must be assessed for suicide risk.

Bipolar I disorder Bipolar II disorder Cyclothymia Substance/medication-induced bipolar and related disorder [7]
Main features
  • Persistent instability of mood involving numerous periods of depression and periods of hypomania
  • Manic or depressive episodes associated with substances/medications


  • ≥ 2 years
  • Remissions last ≤ 2 months
  • During or soon after substance intoxication/withdrawal, or after exposure to a medication
Depressive episodes
  • May be present or absent
  • Depressive symptoms
  • May be present or absent
Psychotic symptoms
  • May be present or absent
  • Absent
  • Absent
  • May be present or absent
  • Significant social or occupational dysfunction
  • May cause significant social or occupational dysfunction during depressive episodes
  • Significant social or occupational dysfunction
  • Significant social or occupational dysfunction

The differential diagnoses listed here are not exhaustive.

Acute treatment for mania and hypomania [8][9][10]

Acute mania is considered a psychiatric emergency and requires immediate management. The goal of acute treatment is resolution of mania and psychosis (if present) as well as preventing any harm to the patient or others. Mood stabilizers are a type of drug used to treat acute mania and/or to prevent relapses of manic or hypomanic episodes.

Antipsychotics are the preferred initial therapy in agitated patients because of their rapid onset of action.

Suicidal patients require immediate management and monitoring to ensure their safety.

Long-term maintenance treatment [8][9]

The goal of maintenance therapy is to prevent future manic episodes, reduce the risk of suicide, and improve social functioning.

In a patient with bipolar disorder, antidepressants should not be used before initiating therapy with mood stabilizers because antidepressants can precipitate a manic episode!

Lithium should not be administered to patients with renal dysfunction! An overdose may result in life-threatening lithium toxicity.

Lithium is the only maintenance drug shown to lower suicide risk.

  1. Sit D. Women and bipolar disorder across the life span. J Am Med Womens Assoc. 2004; 59 (2): p.91-100.
  2. Stovall J. Bipolar Disorder in Adults: Epidemiology and Pathogenesis. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. updated: September 26, 2017. Accessed: December 15, 2017.
  3. Suppes T . Bipolar Disorder in Adults: Assessment and Diagnosis. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. updated: November 1, 2016. Accessed: May 15, 2017.
  4. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (DSM–5). undefined. 2013 . doi: 10.1176/appi.books.9780890425596 . | Open in Read by QxMD
  5. Bassett. Risk assessment and management in bipolar disorders. Med J Aust. undefined; 193 (4): p.S21. doi: 10.5694/j.1326-5377.2010.tb03893.x . | Open in Read by QxMD
  6. Bipolar and Related Disorders. . Accessed: May 15, 2017.
  7. Quello SB et al.. Mood disorders and substance use disorder: a complex comorbidity.. Science & practice perspectives. 2005; 3 (1): p.13-21.
  8. Practice guideline for the treatment of patients with bipolar disorder . Updated: April 1, 2002. Accessed: July 11, 2017.
  9. Guideline watch: Practice guideline for the treatment of patients with bipolar disorder.
  10. Stovall J. Bipolar disorder in adults: Pharmacotherapy for acute mania and hypomania. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. updated: May 17, 2016. Accessed: October 3, 2017.
  11. Yonkers KA et al.. Management of Bipolar Disorder During Pregnancy and the Postpartum Period. Am J Psychiatry. 2004; 161 (4): p.608-620. doi: 10.1176/appi.ajp.161.4.608 . | Open in Read by QxMD
  12. Yatham LN, Kennedy SH, Parikh SV, et al. Canadian Network for Mood and Anxiety Treatments (CANMAT) and International Society for Bipolar Disorders (ISBD) 2018 guidelines for the management of patients with bipolar disorder. Bipolar Disord. 2018; 20 (2): p.97-170. doi: 10.1111/bdi.12609 . | Open in Read by QxMD