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  • Mental Health Issues
    • Anxiety
    • ADHD
    • Bipolar Disorder
    • Depression
    • Grief
    • OCD
    • Personality Disorders
    • PTSD
  • Relationships
    • Dating
    • Marriage
    • Sex & Intimacy
    • Infidelity
    • Relationships 101
  • Wellness
    • Anger
    • Burnout
    • Stress
    • Sleep
    • Meditation
    • Mindfulness
    • Yoga
  • Therapy
    • Starting Therapy
    • Types of Therapy
    • Best Online Therapy Services
    • Online Couples Therapy
    • Online Therapy for Teens
  • Medication
    • Anxiety Medication
    • Depression Medication
    • ADHD Medication
    • Best Online Psychiatrist Options
  • My Mental Health
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    • About Us
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    • Join Our Free Directory
  • What Is Bipolar Disorder?What Is Bipolar Disorder?
  • What Is Bipolar I?What Is Bipolar I?
  • What Is Bipolar II?What Is Bipolar II?
  • What Is the Difference?What Is the Difference?
  • What Causes Bipolar?What Causes Bipolar?
  • How Is It Diagnosed?How Is It Diagnosed?
  • Treatment OptionsTreatment Options
  • Outlook for BipolarOutlook for Bipolar
  • ConclusionConclusion
  • InfographicsInfographics

Bipolar I Vs. Bipolar II: What Is the Difference?

Matt Glowiak PhD CPC headshot

Written by: Matt Glowiak, PhD, LCPC

Heidi-Moawad-MD-Headshot

Reviewed by: Heidi Moawad, MD

Published: September 1, 2023

Although bipolar I and bipolar II have similar symptoms, there are key differences, namely the severity and duration of the manic episodes. Bipolar I is characterized by full-blown manic episodes, while bipolar II involves hypomanic episodes that are less severe. Accordingly, the intensity, duration, and clinical implications may vary significantly.

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What Is Bipolar Disorder?

Bipolar disorder is a diagnosable mental health condition characterized by extremely high highs and low lows. Manic episodes are periods of elevated mood, energy, and impulsivity, whereas depressive episodes include low mood and disinterest.1 Bipolar varies by symptomology and manifests as bipolar I, bipolar II, cyclothymia, rapid cycling bipolar, bipolar with mixed features, bipolar with seasonal pattern, and unspecified bipolar.2

Common symptoms of bipolar disorder include:1

  • Mania or hypomania
  • Depression
  • Mood swings
  • Irritability
  • Sleep disturbances
  • Impulsivity

Manic Vs. Hypomanic Episodes

Manic episodes last at least one week and can require hospitalization due to the intensity of symptoms. Contrastingly, hypomanic episodes last at least four days and do not typically cause severe impairment or necessitate hospitalization, as individuals can often maintain their day-to-day functioning.

Take, for example, impulsive spending. While an evening or several days of reckless spending may be financially damaging, a week or more may lead to losing one’s life savings. With substance use as another example, one may lapse during a hypomanic episode but quickly get “back on the wagon.” A manic episode may lead to full-blown relapse, warranting detoxification and hospitalization.

What Is Bipolar I?

Bipolar I is a subtype of bipolar disorder characterized by intense periods of elevated mood, energy, and activity levels that may prove debilitating, especially if untreated. Those with bipolar I experience at least one manic episode lasting a week or longer.1 One may experience an inflated sense of self-esteem, grandiosity, and heightened confidence. Racing thoughts, rapid speech, and a decreased need for sleep are also common.

While depressive episodes can and do occur for most individuals with bipolar I, they are not considered diagnostic criteria.3 These depressive episodes often follow the typical progression of sadness and a loss of interest or pleasure in previously enjoyed activities. Individuals may experience changes in appetite, sleep disturbances, difficulty concentrating, and suicidality.

Symptoms of bipolar I manic episodes may include:4

  • Decreased need for sleep (e.g., feeling energetic despite significantly less sleep than usual
  • Increased or faster speech
  • Uncontrollable racing thoughts or quickly changing ideas or topics when speaking
  • Distractibility
  • Increased activity (e.g., restlessness, working on several projects at once)
  • Increased risky behavior (e.g., reckless driving, spending sprees)

What Is Bipolar II?

Bipolar II disorder is a subtype of bipolar disorder characterized by recurring hypomanic episodes less severe than full-blown manic episodes seen in bipolar I disorder.1,2 Further, these episodes are shorter, lasting at least four days to meet the criteria of bipolar II, and do not typically cause significant impairment or require hospitalization.

A key distinction of bipolar II is that diagnosis requires someone to have experienced “at least one current or past hypomanic episode and a major depressive episode without a manic episode.”5 Individuals with bipolar II commonly return to more of a baseline between episodes.

Symptoms of bipolar II hypomanic episodes may include:

  • Elevated or irritable mood
  • Increased energy
  • Heightened creativity
  • Racing thoughts
  • Increased talkativeness
  • Engaging in goal-directed activities

Symptoms of bipolar II depressive episodes may include:

  • Persistent feelings of sadness
  • Hopelessness
  • Loss of interest or pleasure in activities
  • Changes in appetite and weight
  • Sleep disturbances
  • Fatigue
  • Difficulty concentrating
  • Feelings of worthlessness
  • Guilt
  • Thoughts of death or suicide

Bipolar I Vs. Bipolar II: What Is the Difference?

The main difference between bipolar I and bipolar II is the intensity of the manic episodes. Bipolar I is characterized by full-blown manic episodes, while bipolar II includes less severe and shorter hypomanic episodes.

Differences between bipolar I and bipolar II include:

Intensity of Manic Episodes

Papercuts sting, but losing a finger is an entirely different experience. A similar comparison can be the varied intensity of manic episodes experienced between bipolar I and II. Neither is desirable, and both compromise well-being. Bipolar II, however, is often more easily managed than bipolar I, though both require adherence to therapy, medication management, and lifestyle changes.

Manic episodes associated with bipolar I may lead to severe psychiatric symptoms, including paranoia, delusions, and hallucinations. Consequently, an individual may become irritable, aggressive, and confused. Accordingly, inpatient hospitalization stays are more common for those with bipolar I than II. While hypomanic episodes with bipolar II may still lead to increased energy, elevated mood, and heightened productivity, individuals often maintain daily functioning. These episodes may even be perceived favorably, as they can enhance creativity, productivity, and sociability.

Prevalence of Major Depressive Episodes

The prevalence of major depression in bipolar I disorder and bipolar II disorder also differs in frequency and duration. In bipolar I disorder, individuals experience full-blown manic episodes, often followed by depressive episodes. The exact prevalence of major depressive episodes varies by person but can be severe and last for an extended period. Consequently, individuals with bipolar I disorder tend to spend more time in a depressed state than a manic state.

In bipolar II disorder, individuals primarily experience recurring depressive and hypomanic episodes of lesser intensity. Depressive episodes in bipolar II are similar to those in bipolar I and can significantly impact well-being and daily functioning. However, individuals with bipolar II spend less time in a manic or hypomanic state than those with bipolar I.

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What Causes Bipolar Disorder?

Although we have come a long way insofar as understanding bipolar disorder and how to treat it, we still have much to learn. In fact, researchers have not determined the general cause of bipolar. Regardless, it is readily apparent that genetics are a common link with the onset and/or exacerbation of current symptoms.

Possible causes of bipolar I and bipolar II include:

Genetics

Bipolar disorder is a progressive condition grounded in genetics. Research suggests a strong genetic component to bipolar, with a higher risk of developing the disorder if there is a family history of the condition. Twin and family studies have shown that the heritability of bipolar disorder is estimated to be around 60-85%, which is substantial.6,7

Researchers have identified several genes that may increase the risk of bipolar disorder (i.e., G72/DAOA, DISC1, NRG1, TPH2, BDNF, 5-HTT, & DAT1), although the specific genetic mechanisms are not fully understood.8 These genes are involved in various processes related to brain function, neurotransmitter regulation, and circadian rhythm.

Substance Abuse

Substance abuse and bipolar disorder can be closely intertwined, although the relationship between the two is complex and multifaceted. Those with bipolar disorder are at a higher risk of developing alcoholism and substance use disorders.9

Substance abuse disrupts brain chemistry, leading to neurotransmitter imbalances that facilitate mood regulation. These shifts can trigger or exacerbate manic and depressive episodes. Contrastingly, some may turn to substance use to alleviate the distressing symptoms of depression or temporarily enhance their mood during manic episodes.

Severe Stress

Severe stress can play a role in triggering the onset of bipolar disorder or exacerbating symptoms in individuals who already have a genetic predisposition to the condition.10 Stress alone is not the sole cause of bipolar disorder but can play a substantial role in its development.

Stressful life events, such as trauma or major life changes, can disrupt the balance of brain chemicals and neurotransmitters that influence mood regulation. This disruption can potentially trigger a manic or depressive episode in individuals vulnerable to bipolar disorder.

Moreover, stress can also influence the course and severity of bipolar disorder in diagnosed individuals. High stress levels can lead to more frequent and intense mood swings, lengthening the duration of episodes and increasing the risk of relapse. Stress can also interfere with sleep patterns, exacerbating symptoms and making it more challenging to manage the condition effectively.

How Are Bipolar I & Bipolar II Diagnosed?

Qualified healthcare professionals can diagnose bipolar I and bipolar II. The combined assessment of professionals specializing in mental health conditions yields the most thorough and accurate diagnosis of bipolar disorder. This team may include psychiatrists, clinical psychologists, mental health counselors, physicians, and others.

Diagnosis depends on a thorough assessment of an individual’s symptoms, medical history, and family history. A healthcare provider may also conduct a physical exam and order lab tests to rule out any other medical conditions possibly contributing to symptoms.

To aid in understanding the diagnostic criteria for bipolar I and bipolar II, here is a side-by-side comparison:

Bipolar I DisorderBipolar II Disorder
Experienced at least one manic episode lasting for at least one weekExperienced at least one hypomanic episode lasting for at least four days
Depressive episodes may or may not be presentExperienced at least one major depressive episode
May include psychotic symptoms (i.e., hallucinations, delusions, paranoia)Typically, does not include psychotic symptoms
Symptoms may prove extremely disruptive to daily functioningSymptoms have less of an overall negative impact and may even seemingly enhance functioning
Often requires inpatient hospitalizationHospitalization is less common
Symptoms often lead to significant consequences (e.g., social, financial, legal, etc.)Symptoms are less likely to lead to significant consequences (e.g., social, financial, legal, etc.)
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How Is Bipolar Disorder Treated?

Although there is currently no known cure for bipolar I or II, there are many treatments for bipolar that, with strict adherence, allow individuals to lead happy, productive lives. Effective treatment is often an intentional and consistent combination of partaking in therapy, medication management, and appropriate lifestyle changes.

It is important for individuals with bipolar disorder to work closely with their healthcare provider to develop an individualized treatment plan that addresses their specific needs and goals.

Common treatment approaches for bipolar I and bipolar II include:

  • Medication: Medications for bipolar help stabilize mood and manage the episodes of mania and depression. Providers may prescribe mood stabilizers, such as lithium, anticonvulsants (e.g., valproate, lamotrigine), and atypical antipsychotics.
  • Cognitive behavioral therapy (CBT): CBT for bipolar is a form of psychotherapy that focuses on identifying and modifying negative thought patterns and behaviors. It assists in developing effective coping strategies, stress management, and overall mood regulation.
  • Mindfulness-based therapies: Mindfulness-based stress reduction (MBSR) or mindfulness-based cognitive therapy (MBCT) can help individuals learn and develop skills for managing stress, regulating emotions, and enhancing overall well-being.
  • Dialectical behavior therapy (DBT): DBT is a comprehensive therapy that combines elements of CBT and mindfulness. The client and therapist focus on emotional regulation, distress tolerance, and interpersonal effectiveness.
  • Interpersonal and social rhythm therapy (IPSRT): IPSRT was created specifically for individuals with bipolar disorder. It helps stabilize daily routines while regulating social rhythms to establish a consistent sleep-wake schedule. These techniques are especially beneficial for those who experience bipolar and insomnia concurrently.
  • Electroconvulsive therapy (ECT): In more severe cases of bipolar disorder, particularly bipolar I, ECT may be a treatment option. ECT involves controlled electric currents to the brain to induce a therapeutic seizure and alleviate symptoms. Given mixed thoughts, emotions, and ethical concerns, ECT is often a last-ditch effort.
  • Transcranial magnetic stimulation (TMS): TMS is a relatively newer therapy that utilizes magnetic fields to stimulate various nerve cells in the brain. Its non-invasive nature makes TMS more appealing than ECT while eliciting more desirable results.
  • Lifestyle modifications: These may include maintaining a regular sleep schedule, avoiding alcohol and substance abuse, managing stress effectively, and engaging in healthy lifestyle habits such as exercise and a balanced diet.

Bipolar I Vs. Bipolar II: Is Treatment the Same?

With bipolar I, treatment often focuses on managing the acute symptoms of mania and preventing relapse. Medications may help stabilize mood and reduce the intensity and frequency of manic episodes. Due to the potential for more severe symptoms and the higher risk of hospitalization, treatment may require more invasive and immediate intervention. With bipolar II disorder, the emphasis is often on managing depressive episodes.

Individuals with bipolar II may benefit more from therapeutic approaches that target depressive symptoms and help develop strategies for coping with milder hypomanic episodes. Ultimately, treatment plans for either condition are individualized based on the unique needs and symptoms of the individual.

Outlook for Bipolar I & Bipolar II

Both types of bipolar disorder can be challenging to manage but can be successfully treated, despite neither having a known cure. Many who effectively engage in therapy, medication management, and healthy lifestyle adjustments experience significant improvement in symptom control and overall stability.

The outlook for bipolar disorder varies from person to person and is influenced by various factors, such as the severity of symptoms, individual response to treatment, and co-occurring conditions. Proper diagnosis followed by a treatment plan is crucial for managing the condition effectively.

Final Thoughts

Whether you are struggling with bipolar I or II, you are not alone. Others struggle with the disorder, and those willing to provide support are ready to help. The first step begins with awareness. Despite a potentially long and winding road ahead, there is still much to which you may look forward along the path to recovery.

Additional Resources

Education is just the first step on our path to improved mental health and emotional wellness. To help our readers take the next step in their journey, Choosing Therapy has partnered with leaders in mental health and wellness. Choosing Therapy may be compensated for marketing by the companies mentioned below.

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For Further Reading

  • National Alliance on Mental Illness: Bipolar Disorder
  • Depression and Bipolar Support Alliance (DBSA)
  • Mental Health America (MHA)
  • National Alliance on Mental Illness (NAMI)
  • Substance Abuse and Mental Health Services Administration (SAMHSA)
  • Hope for the Day

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What Is Bipolar I? What Is Bipolar II? Bipolar I Vs. Bipolar II: What is the Difference? How Is Bipolar Disorder Treated?

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Sources Update History

Choosing Therapy strives to provide our readers with mental health content that is accurate and actionable. We have high standards for what can be cited within our articles. Acceptable sources include government agencies, universities and colleges, scholarly journals, industry and professional associations, and other high-integrity sources of mental health journalism. Learn more by reviewing our full editorial policy.

  • American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). https://doi.org/10.1176/appi.books.9780890425596

  • Mind. (2022). Bipolar. Retrieved from https://www.mind.org.uk/information-support/types-of-mental-health-problems/bipolar-disorder/types-of-bipolar/

  • National Alliance on Mental Illness. (2017). Bipolar disorder. Retrieved from https://www.nami.org/About-Mental-Illness/Mental-Health-Conditions/Bipolar-Disorder

  • American Psychiatric Association. (2021). What are bipolar disorders? Retrieved from https://www.psychiatry.org/patients-families/bipolar-disorders/what-are-bipolar-disorders

  • Jain A, Mitra P. (2023). Bipolar Disorder. In: StatPearls [Internet]. Available from https://www.ncbi.nlm.nih.gov/books/NBK558998/#

  • Robinson, N., & Bergen, S. E. (2021). Environmental risk factors for schizophrenia and bipolar disorder and their relationship to genetic risk: Current knowledge and future directions. Frontiers in Genetics, 12. https://doi.org/10.3389/fgene.2021.686666

  • Smoller, J. W., & Finn, C. (2003). Family, twin, and adoption studies of bipolar disorder. American Journal of Medical Genetics Part C: Seminars in Medical Genetics, 123C(1), 48–58. https://doi.org/10.1002/ajmg.c.20013

  • Cold Spring Harbor Laboratory. (n.d.). Bipolar disorder gene candidates. Retrieved from https://dnalc.cshl.edu/view/1484-Bipolar-Disorder-Candidate-Genes.html

  • Salloum, I. M., & Brown, E. S. (2017). Management of comorbid bipolar disorder and substance use disorders. American Journal of Drug and Alcohol Abuse, 43(4), 366–376. https://doi.org/10.1080/00952990.2017.1292279

  • Koenders, M., et al. (2014). Stressful life events in bipolar I and II disorder: Cause or consequence of mood symptoms? Journal of Affective Disorders, 161, 55–64. https://doi.org/10.1016/j.jad.2014.02.036

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We regularly update the articles on ChoosingTherapy.com to ensure we continue to reflect scientific consensus on the topics we cover, to incorporate new research into our articles, and to better answer our audience’s questions. When our content undergoes a significant revision, we summarize the changes that were made and the date on which they occurred. We also record the authors and medical reviewers who contributed to previous versions of the article. Read more about our editorial policies here.

September 1, 2023
Author: Matt Glowiack, PhD, LCPC
Reviewer: Heidi Moawad, MD
Primary Changes: Rewritten to include more detail and a broader range of topics. Reviewed and added relevant resources.
September 9, 2020
Author: Michael Pipich, LMFT
Reviewer: Meera Patel, DO
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  • What Is Bipolar Disorder?What Is Bipolar Disorder?
  • What Is Bipolar I?What Is Bipolar I?
  • What Is Bipolar II?What Is Bipolar II?
  • What Is the Difference?What Is the Difference?
  • What Causes Bipolar?What Causes Bipolar?
  • How Is It Diagnosed?How Is It Diagnosed?
  • Treatment OptionsTreatment Options
  • Outlook for BipolarOutlook for Bipolar
  • ConclusionConclusion
  • InfographicsInfographics
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