Bipolar disorder is a mental health condition that causes extreme shifts in mood, energy, and daily functioning. According to the National Institute of Mental Health (NIMH), an estimated 2.8% of U.S. adults had bipolar disorder in the past year.
There are two main types—bipolar 1 and bipolar 2—which share similarities but differ in key ways Whether you’re personally going through it or supporting someone who is, understanding the differences between these two types can help with early diagnosis and treatment.
Key Takeaways
Bipolar disorder affects about 2.8% of U.S. adults each year. Symptoms typically appear in late adolescence or early adulthood. On average, it takes about 10 years from symptom onset to receive an accurate diagnosis.
The main difference between bipolar 1 and bipolar 2 is the severity of elevated mood episodes. Bipolar 1 involves full manic episodes typically lasting for at least 7days, while bipolar 2 involves milder hypomanic episodes, along with more frequent depressive episodes.
Both types are treatable with a combination of mood-stabilizing medications, psychotherapy, and lifestyle changes. If you’re experiencing significant mood changes that interfere with your daily life, speaking with a psychiatrist can be an important first step toward getting the right diagnosis and treatment plan.
What Is Bipolar Disorder?
Bipolar disorder is a chronic mood disorder characterized by episodes of unusually elevated mood (mania or hypomania) and periods of depression. These mood episodes differ from typical mood changes and can significantly affect a person’s ability to work, maintain relationships, and handle daily responsibilities.
The condition typically develops in late adolescence or early adulthood, with a median age of onset around 25 years. Research published in the Archives of General Psychiatry found that lifetime prevalence estimates are approximately 1.0% for bipolar 1 and 1.1% for bipolar 2. Both genetic and environmental factors can contribute to its development, and having a first-degree relative with bipolar disorder also increases your risk.
What Is Bipolar 1 Disorder?
Bipolar 1 disorder is characterized by the presence of at least one manic episode.A manic episode is a period of elevated, expansive, or irritable mood and increased energy or activity that lasts at least 7 consecutive days, or any duration if hospitalization is required.
According to the American Psychiatric Association’s DSM-5, a manic episode must represent a change from usual behaviour. And symptoms must be severe enough to cause dysfunction in daily life, work, family, social activities, or responsibilities.
Symptoms of a Manic Episode
Inflated self-esteem or feelings of grandiosity
Significantly reduced need for sleep (feeling rested after only a few hours)
Rapid speech or racing thoughts
Increased goal-directed activity or physical restlessness
Impulsive or high-risk behaviors, such as reckless spending, risky sexual behavior, or poor business decisions
In some cases, psychotic symptoms such as delusions or hallucinations
People with bipolar 1 may also experience depressive episodes, but usually they are not required for diagnosis. Manic episodes can be severe and may require hospitalization, significantly affecting daily life.
What Is Bipolar 2 Disorder?
Bipolar 2 disorder is characterized by at least one hypomanic episode and at least one major depressive episode. Unlike bipolar 1, people with bipolar 2 do not usually experience a full manic episode. If a full manic episode occurs at any point, the diagnosis changes to bipolar 1.
Hypomania shares many of the same symptoms as mania—elevated mood, increased energy, reduced need for sleep—but it is less severe.
Hypomanic episodes last at least 4 consecutive days, do not typically require hospitalization, and do not include psychotic symptoms. In fact, some people experiencing hypomania may feel more productive or energized than usual, which can make it harder to recognize as a symptom.
One key difference in bipolar 2 is that the depressive episodes tend to be more frequent and longer-lasting compared to bipolar 1.
Research suggests that the ratio of depressive to hypomanic episodes in bipolar 2 is significantly higher. This means that people with bipolar 2 often spend more time in depressive states. This may also contribute to why bipolar 2 is frequently misdiagnosed as major depressive disorder, especially because people often seek help during depressive episodes rather than during periods of hypomania.
Bipolar 1 vs. Bipolar 2: Key Differences at a Glance
While both conditions involve mood episodes, the nature and severity of those episodes differ in important clinical ways:
Elevated mood episodes: Bipolar 1 requires at least one full manic episode (7+ days or hospitalization). Bipolar 2 involves hypomanic episodes (4+ days) that are usually less severe and shorter.
Depressive episodes: Not required for a bipolar 1 diagnosis, but required for bipolar 2. People with bipolar 2 often experience longer-lasting and more frequent depression.
Psychosis risk: Manic episodes in bipolar 1 may include psychotic symptoms such as delusions or hallucinations. Hypomanic episodes in bipolar 2 do not involve psychosis.
Hospitalization: Manic episodes in bipolar 1 may frequently require hospital admission. Hypomanic episodes in bipolar 2 typically do not.
Functional impact: Bipolar 1 can involve severe, acute disruption during manic episodes. In bipolar 2, disruptions are often caused by repeated and longer-lasting depressive episodes.
It’s a common misconception that bipolar 2 is simply a “milder” form of bipolar 1. While bipolar 2 involves less severe elevated mood episodes, depressive symptoms can also be severely disabling. According to the Cleveland Clinic, both conditions are serious and carry significant risks, including an increased risk of suicide.
How Is Bipolar Disorder Diagnosed?
A psychiatrist or other qualified mental health professional diagnoses bipolar disorder through a comprehensive clinical evaluation.
There is no blood test or brain scan that can confirm bipolar disorder. The diagnosis relies on a detailed review of your symptoms, medical history, family history, and the pattern of your mood episodes over time.
Getting an accurate diagnosis can take time. Research from the Depression and Bipolar Support Alliance suggests that people with bipolar disorder may experience delays of up to 10 years before receiving an accurate diagnosis.
Bipolar 2 can be particularly challenging to identify because hypomanic episodes may go unrecognized, and depressive episodes can resemble major depressive disorder.
Treatment Options for Bipolar 1 and Bipolar 2
Bipolar disorders are treatable, and many people often benefit from a combination of medication, psychotherapy, and lifestyle changes. However, treatment plans may differ depending on the type and severity of episodes.
Medications
According to the NIMH, commonly prescribed medications for bipolar disorder include mood stabilizers such as lithium or valproate, which may help reduce the frequency or severity of mood episodes.
Atypical antipsychotics may also be used, particularly during acute manic episodes.
For bipolar 2, treatment often focuses on managing depressive episodes. This may involve cautious use of certain antidepressants along with mood stabilizers to help reduce the risk of hypomania.
Psychotherapy
Therapy plays an important role in managing bipolar disorder.
Approaches like cognitive behavioral therapy (CBT), interpersonal and social rhythm therapy, and psychoeducation help people recognize early warning signs of mood episodes, build coping strategies, and maintain more stable daily routines. Therapy is typically used alongside medication rather than as a replacement.
Lifestyle Strategies
Consistent sleep schedules, regular physical activity, stress management, and avoiding alcohol and recreational drugs may all support mood stability. Some people find that tracking their mood patterns can help them identify triggers and catch early warning signs before episodes escalate.
When to Seek Medical Attention
It may be helpful to speak with a mental health provider for further evaluation, if you’re experiencing:
Periods of unusually elevated mood, energy, or irritability that feel out of character
Depressive episodes that make it difficult to function at work, school, or in relationships
Rapid mood swings that alternate between emotional highs and lows
Impulsive or risky behaviors during periods of elevated mood
A family history of bipolar disorder, especially if you’re also experiencing mood symptoms
Blossom Health can connect you with licensed psychiatric providers through virtual, insurance-covered appointments. Get started now to book your first virtual visit with the psychiatrist that fits your needs, schedule, and insurance.
Medical Disclaimer
This article is for educational purposes only and does not constitute medical advice. The information provided should not replace consultation with a qualified healthcare provider. Individual responses to medications can vary significantly, and what applies to one person may not be the same for another.
Always consult with your doctor or pharmacist before making any decisions about medication changes, discontinuation, or interactions with other substances. If you’re experiencing concerning symptoms or side effects, please seek professional help from a healthcare provider.
In case of a medical emergency, contact your local emergency services immediately or call 911. For mental health emergencies, contact the National Suicide Prevention Lifeline at 988.Sources
Sources
National Institute of Mental Health (NIMH). Bipolar Disorder Statistics. https://www.nimh.nih.gov/health/statistics/bipolar-disorder
Merikangas, K. R., Akiskal, H. S., Angst, J., Greenberg, P. E., Hirschfeld, R. M., Petukhova, M., & Kessler, R. C. (2007). Lifetime and 12-month prevalence of bipolar spectrum disorder in the National Comorbidity Survey replication. Archives of general psychiatry, 64(5), 543–552. https://doi.org/10.1001/archpsyc.64.5.543
Depression and Bipolar Support Alliance. Bipolar Disorder Statistics. https://www.dbsalliance.org/education/bipolar-disorder/bipolar-disorder-statistics/
American Psychiatric Association. (April 2024). What Are Bipolar Disorders? https://www.psychiatry.org/patients-families/bipolar-disorders/what-are-bipolar-disorders
National Institute of Mental Health (NIMH). (December 2024). Bipolar Disorder. https://www.nimh.nih.gov/health/topics/bipolar-disorder
Cleveland Clinic. (February 22, 2023). Bipolar 1 vs. Bipolar 2. https://health.clevelandclinic.org/bipolar-1-vs-2
Datto, C., Pottorf, W. J., Feeley, L., LaPorte, S., & Liss, C. (2016). Bipolar II compared with bipolar I disorder: baseline characteristics and treatment response to quetiapine in a pooled analysis of five placebo-controlled clinical trials of acute bipolar depression. Annals of general psychiatry, 15, 9. https://doi.org/10.1186/s12991-016-0096-0
Rowland, T. A., & Marwaha, S. (2018). Epidemiology and risk factors for bipolar disorder. Therapeutic advances in psychopharmacology, 8(9), 251–269. https://doi.org/10.1177/2045125318769235 Jain A, Mitra P. (February 20, 2023). Bipolar Disorder. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK558998/
