The main difference in bipolar 1 vs bipolar 2 is the type of “high.” Bipolar I disorder involves at least one full manic episode, which lasts at least a week or is severe enough to need hospital care, while bipolar II disorder involves at least one hypomanic episode (a milder high) and at least one major depressive episode, but never full mania. Bipolar II is not simply a milder version of bipolar I; its depressive episodes can be long and disabling.
Both are lifelong but treatable conditions. Below, we break down how each type is defined, how symptoms compare and what treatment looks like, so you can have a more informed conversation with a provider.
What Is Bipolar Disorder?
According to the National Institute of Mental Health (NIMH), bipolar disorder is a mental illness that causes clear shifts in a person’s mood, energy, activity levels and concentration. These shifts include “up” periods (mania or hypomania) and “down” periods (depression). It was once called manic-depressive illness.
Bipolar disorder is less common than depression or anxiety, but it has a large impact. NIMH estimates that 2.8% of U.S. adults had bipolar disorder in the past year and 4.4% will have it at some point in their lives. Of adults with bipolar disorder, 82.9% had serious impairment, the highest share among mood disorders. For a broader overview, visit our bipolar disorder hub.
Clinicians recognize three main types: bipolar I, bipolar II and cyclothymic disorder. The first two are the most common diagnoses and the ones people most often compare.
Bipolar 1 vs Bipolar 2 at a Glance
- Type of high: Bipolar I involves full mania. Bipolar II involves hypomania only.
- Length of the high: A manic episode lasts at least 7 days (or any length if hospitalization is needed). The American Psychiatric Association notes hypomania requires symptoms for at least four days in a row.
- Depression: Bipolar II requires at least one major depressive episode. Depression is common in bipolar I but not required for the diagnosis.
- Psychosis: Mania can include hallucinations or delusions. Hypomania does not.
- Hospitalization: Mania may require a hospital stay. Hypomania, by definition, does not.
- Daily functioning: Mania causes marked problems at work, school or in relationships. Hypomania does not cause major problems with daily functioning, according to the APA.
Bipolar I Disorder: Defined by Mania
A person with bipolar I has had at least one manic episode. NIMH describes manic episodes in bipolar I as lasting at least 7 days, most of the day and nearly every day, or being so severe that the person needs hospital care. Depressive episodes lasting at least two weeks usually occur as well, and some people have periods of hypomania or stable mood in between.
Signs of a Manic Episode
- Feeling very “up,” elated or unusually irritable
- Much more energy and activity than usual
- Needing little sleep without feeling tired
- Talking fast and jumping between racing thoughts
- Feeling unusually important, powerful or talented
- Doing more risky or impulsive things than usual
Mayo Clinic explains that mania is severe enough to cause noticeable problems at work, school or in relationships, may trigger psychosis and can require hospitalization. For a closer look at these symptoms, read our guide to the signs of mania and hypomania. If someone is in danger or unable to stay safe, call 911 or see our guide on what to do in a mental health crisis.
Bipolar II Disorder: Hypomania and Depression
A person with bipolar II has had at least one hypomanic episode and at least one major depressive episode, but has never had a full manic episode. Hypomania has similar symptoms to mania but they are less intense and do not include psychosis.
Why Bipolar II Is Not “Bipolar Lite”
It’s easy to assume that bipolar II is the “easier” type. Mayo Clinic is clear that bipolar II is not a milder form of bipolar I, but a separate diagnosis. NIMH notes that many people with bipolar II have long periods of depression, and depressive episodes can bring sadness, hopelessness, trouble concentrating and thoughts of death or suicide.
Why It’s Often Mistaken for Depression
Hypomania may feel like a productive, energetic stretch rather than a symptom. Cleveland Clinic notes that because hypomanic episodes don’t stand out as much, some people with bipolar II are first diagnosed, or misdiagnosed, with depression. That matters because NIMH warns antidepressants are not used alone in bipolar disorder, since they can trigger a manic episode. If you’ve been treated for depression and have also had periods of high energy and little need for sleep, tell your provider.
If you are having thoughts of suicide, call or text the 988 Suicide & Crisis Lifeline. In an emergency, call 911.
What About Cyclothymic Disorder?
Cyclothymic disorder involves repeated hypomanic and depressive symptoms that aren’t intense enough or long-lasting enough to count as full episodes. Mayo Clinic notes symptoms must last at least two years in adults (one year in children and teens).
What Bipolar I and II Have in Common
- Onset: Mayo Clinic says bipolar disorder often starts in the teen years or early 20s, and the APA reports the average age of onset is in the mid-20s.
- Family links: The APA notes that 80 to 90 percent of people with bipolar disorder have a relative with bipolar disorder or depression.
- Co-occurring conditions: Anxiety disorders, ADHD and substance use disorders are common with both types. The APA adds that drugs and alcohol may trigger mood episodes in vulnerable people. Learn more in our guide to bipolar disorder and substance use.
- Diagnosis: Providers look at the severity, length and frequency of symptoms over your lifetime, plus family history, and may do a physical exam and tests to rule out other causes.
Treatment for Bipolar I and Bipolar II
When it comes to bipolar 1 vs bipolar 2 treatment, the overall approach is similar: both types are treated with a combination of medication and therapy, and long-term, consistent treatment is key. According to NIMH and the APA:
- Medication: Mood stabilizers such as lithium and valproate, and atypical antipsychotics, are commonly used. Cleveland Clinic notes people with bipolar I may need additional medication to address psychosis. Read more about bipolar medications.
- Psychotherapy: CBT, family-focused therapy and interpersonal and social rhythm therapy can help people manage symptoms and stick with treatment.
- Brain stimulation: Electroconvulsive therapy (ECT) may help when other treatments haven’t worked.
- Daily routines: Regular sleep, meals and exercise, tracking your moods and avoiding alcohol and drugs all support stability.
Frequently Asked Questions
Which is worse, bipolar 1 or bipolar 2?
Neither is simply “worse.” Bipolar I involves more severe highs that can include psychosis, while bipolar II often involves longer, more frequent depression. Both need ongoing treatment.
Can bipolar 2 turn into bipolar 1?
If a person with a bipolar II diagnosis later has a full manic episode, the diagnosis would change to bipolar I. That is one reason regular follow-up with a provider matters.
How long does a manic or hypomanic episode last?
A manic episode lasts at least seven days or requires hospitalization. A hypomanic episode lasts at least four days in a row.
Can you have bipolar disorder without depression?
Bipolar I can be diagnosed after a single manic episode, even without a depressive episode. Bipolar II always includes at least one major depressive episode.
Get Help for Bipolar Disorder in Lancaster, PA
Whether you are living with bipolar I or bipolar II, the right support makes stability possible. The Ranch Pennsylvania Outpatient Services offers mental health treatment with psychiatric evaluation, medication management and therapies like CBT and DBT. Choose our partial hospitalization program for full-day support or our intensive outpatient program while living at home. Learn about bipolar treatment in Pennsylvania or verify your insurance. Our admissions team is available 24/7, and calls are free and confidential.
