Bipolar II Disorder

What Is Bipolar II Disorder?

Bipolar II disorder (pronounced "bipolar two") is a form of mental illness. Bipolar II is similar to bipolar I disorder, with moods cycling between high and low over time.

However, in bipolar II disorder, the "up" moods never reach full-blown mania. The less-intense elevated moods in bipolar II disorder are called hypomanic episodes, or hypomania.

A person affected by bipolar II disorder has had at least one hypomanic episode in his or her life. Most people with bipolar II disorder suffer more often from episodes of depression. This is where the term "manic depression" comes from.


A Visual Guide to Understanding Bipolar Disorder

Who Is at Risk for Bipolar II Disorder?

Virtually anyone can develop bipolar II disorder. About 2.5% of the U.S. population suffers from some form of bipolar disorder - nearly 6 million people.


What Are the Symptoms of Bipolar II Disorder?

During a hypomanic episode, elevated mood can manifest itself as either euphoria (feeling "high") or as irritability.

Symptoms during hypomanic episodes include:

  • Flying suddenly from one idea to the next
  • Having exaggerated self confidence
  • Rapid, "pressured" (uninterruptible) and loud speech
  • Increased energy, with hyperactivity and a decreased need for sleep

People experiencing hypomanic episodes are often quite pleasant to be around. They can often seem like the "life of the party" -- making jokes, taking an intense interest in other people and activities, and infecting others with their positive mood.

What's so bad about that, you might ask? Hypomania can also lead to erratic and unhealthy behavior. Hypomanic episodes can sometimes progress onward to full manias that affect a person's ability to function (bipolar I disorder). In mania, people might spend money they don't have, seek out sex with people they normally wouldn't, and engage in other impulsive or risky behaviors with the potential for dangerous consequences.




Depressive episodes in bipolar II disorder are similar to "regular" clinical depression, with depressed mood, loss of pleasure, low energy and activity, feelings of guilt or worthlessness, and thoughts of suicide. Depressive symptoms of bipolar disorder can last weeks, months, or rarely years.

What Are the Treatments for Bipolar II Disorder?

Hypomania often masquerades as happiness and relentless optimism. When hypomania is not causing unhealthy behavior, it often may go unnoticed and therefore remain untreated. This is in contrast to full mania, which by definition causes problems in functioning and requires treatment with medications and possibly hospitalizations.

People with bipolar II disorder can benefit from preventive drugs that level out moods over the long term. These prevent the negative consequences of hypomania, and also help to prevent episodes of depression.

Mood Stabilizers

Lithium: This simple metal in pill form is highly effective at controlling mood swings (particularly highs) in bipolar disorder. Lithium has been used for more than 60 years to treat bipolar disorder. Lithium can take weeks to work fully, making it better for long-term treatment than for acute hypomanic episodes. Blood levels of lithium and other laboratory tests (such as kidney and thyroid functioning) must be monitored periodically to avoid side effects.

Carbamazepine (Tegretol): This antiseizure drug has been used to treat mania since the 1970s. Its possible value for treating bipolar depression, or preventing future highs and lows, is less well-established. Blood tests to monitor liver functioning and white blood cell counts also are periodically necessary.

Lamotrigine (Lamictal): This drug is approved by the FDA for the maintenance treatment of adults with bipolar disorder. It has been found to help delay bouts of mood episodes of depression, mania, hypomania (a milder form of mania), and mixed episodes in people being treated with standard therapy. It is especially helpful in preventing lows.


Valproate (Depakote): This antiseizure drug also works to level out moods. It has a more rapid onset of action than lithium, and it can also be used "off label" for prevention of highs and lows.

Some other antiseizure medications, such as oxcarbazepine (Trileptal), are also sometimes prescribed as "experimental" (less-proven) treatments for mood symptoms or associated features in people with bipolar disorder.


By definition, hypomanic episodes do not involve psychosis and do not interfere with functioning. Antipsychotic drugs, such as aripiprazole (Abilify), cariprazine (Vraylar), quetiapine (Seroquel), asenapine (Saphris), olanzapine (Zyprexa), risperidone (Risperdal), and ziprasidone (Geodon) and others, are nevertheless sometimes used in hypomania and some (notably, Seroquel) are used for depression in bipolar II disorder.


This class of drugs includes alprazolam (Xanax), diazepam (Valium), and lorazepam (Ativan) and is commonly referred to as minor tranquilizers. They are used for short-term control of acute symptoms associated with hypomania such as insomnia or agitation.


Seroquel and Seroquel XR are the only medications FDA-approved specifically for bipolar II depression. Common antidepressants such as fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft) are also sometimes used in bipolar II depression, and are thought to be less likely to cause or worsen hypomania than is the case in bipolar I disorder. Psychotherapy, such as cognitive-behavioral therapy, may also help.

Because bipolar II disorder typically involves recurrent episodes, continuous and ongoing treatment with medicines is often recommended for relapse prevention.

Can Bipolar II Disorder Be Prevented?

The causes of bipolar disorder are not well understood. It's not known if bipolar II disorder can be prevented entirely.

It is possible to reduce the risk for developing future episodes of hypomania or depression once bipolar disorder has developed. Regular therapy sessions with a psychologist or social worker, in combination with medication, can help efforts to stabilize mood, leading to fewer hospitalizations and feeling better overall. Psychotherapy can help people better recognize the warning signs of a developing relapse before it takes hold, and can also help to ensure that prescribed medicines are being taken properly.


How Is Bipolar II Disorder Different From Other Types of Bipolar Disorder?

People with bipolar I disorder experience full mania -- a severe, abnormally elevated mood with erratic behavior. Manic symptoms lead to serious disruptions in life, causing legal or major personal problems.

In bipolar II disorder, the symptoms of elevated mood never reach full-blown mania. Hypomania in bipolar II is a milder form of mood elevation. However, the depressive episodes of bipolar II disorder are often longer-lasting and may be even more severe than in bipolar I disorder. Therefore, bipolar II disorder is not simply a "milder" overall form of bipolar disorder.

WebMD Medical Reference Reviewed by Jennifer Casarella on November 25, 2019


Moore, D. Handbook of Medical Psychiatry, Mosby, 2004.
National Institute of Mental Health web site: "Bipolar Disorder."
Medical News Today: "Study Identifies Predictors Of Bipolar Disorders Risk."
WebMD Medical Reference from Healthwise: "Bipolar Disorder -- What Increases Your Risk."

© 2019 WebMD, LLC. All rights reserved.