What is bipolar disorder?

Bipolar disorder is a mental health condition. People with bipolar disorder can alternate between periods of positive moods, called mania, and negative moods, called depression. These mood shifts can occur suddenly. About 2.8 percent of the adolescent and adult U.S. population have bipolar disorder, according to the National Institute of Mental Health.

Bipolar disorder and its causes aren’t well-understood. That said, researchers have noted a possible connection between family history and bipolar disorder. This suggests there may be a genetic component to the disorder.

Keep reading to learn more about this connection and about bipolar disorder.

While researchers don’t fully understand the causes of bipolar disorder, they have identified some risk factors. One of the strongest risk factors is a family history of the disorder. This connection may be due to certain genes.

Adults who have relatives with the disorder have an average tenfold increase in risk of developing the disorder, according to a 2009 review. Your risk further increases if the family member with the condition is a close relative. That means if your parent has bipolar disorder, you have a greater chance of developing it than someone whose great aunt has the condition.

Genetic factors account for about 60 to 80 percent of the cause of bipolar disorder. That means that heredity isn’t the only cause of bipolar disorder. It also means that if you have a family history of the disorder, you won’t definitely develop it. Most family members of someone with bipolar disorder won’t develop the condition.

In addition to heredity, researchers believe there are other risk factors for bipolar disorder.

Brain structure

There may be subtle differences in brain size and activity in people with bipolar disorder. Concussions and traumatic head injuries may also increase a person’s risk of developing bipolar disorder.

Environmental factors

A stressful event often triggers the onset, or start, of bipolar disorder. This event could be a high-stress occurrence related to work or personal life. A sudden, major life change, such as the death of a loved one or a physical injury, could also trigger the onset. People who have bipolar disorder typically find it helpful to control stress in their lives.

Seasonal factors may trigger the onset of bipolar disorder episodes. The change from winter to spring, in particular, is a strong trigger. This is because the quick increase in the number of hours of bright sunshine during the day affects the pineal gland. This, in turn, may influence development of depression and mania.

Other triggers can include heavy drug or alcohol use and a lack of sleep. And in certain cases, bipolar disorder in women can be triggered during the period after giving birth. This generally occurs in women who are biologically inclined to developing it in the first place. Pregnancy itself, however, isn’t usually the underlying cause of bipolar disorder.


If my parent has bipolar disorder, should I have my doctor regularly screen me for the disorder?

Anonymous patient


Screening for bipolar disorder by your family doctor can be a good idea. More importantly, you should talk to people you trust who seem to know you the best, such as family members or friends. Loved ones generally notice the symptoms of bipolar disorder before they’re out of control and hospitalization is necessary. If your family members or trusted friends are telling you that your behavior is strange and not how you usually act, this might be a good time to make an appointment with your doctor. Consider taking along a family member or trusted friend who can share their observations with your doctor.

Timothy J. Legg, PhD, PsyD, PMHNP-BCAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.
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If you think you or someone in your family may have bipolar disorder, it’s helpful to know what symptoms to look for. The type of bipolar disorder a person has determines the symptoms they will experience. In general, the main symptoms of the different types of bipolar disorder are mania and depression.

The symptoms of bipolar mania include:

  • restless and impulsive behavior
  • poor judgement
  • an unrealistic perception of abilities
  • happiness, even to the point of euphoria
  • agitation
  • jumpiness
  • participating in risky behavior, such as gambling, drunk driving, or impulsive sex
  • talking quickly
  • thinking quickly

The symptoms of bipolar depression are similar to the symptoms of regular depression. They include:

  • intense fatigue
  • prolonged, extreme sadness
  • talking slowly
  • issues with proper decision-making and focus
  • a poor appetite
  • hopelessness
  • thoughts of self-harm, including suicide
  • withdrawal from friends and families
  • a loss of interest in activities and hobbies

The average age when bipolar disorder develops is about 25 years. Bipolar disorder can start at any age, though. Some people experience their first symptoms as a child. Others have the first symptoms later in their adult life.

Getting a proper diagnosis can take years. This is because people may mistake it for another disorder, or may not report their symptoms.

Your doctor may use several methods to diagnose bipolar disorder:

  • Examine your medical history and symptoms.
  • Complete a comprehensive mental health evaluation. This may include giving you a questionnaire or asking you to keep a record of your mood patterns
  • Interview family members, close friends, and other people you frequently see, with your permission.
  • Physically examine you to rule out other causes of symptoms, such as hyperthyroidism, or an overactive thyroid.

Treatment typically involves medication, behavioral therapy, or a combination of the two.


Several drugs effectively treat bipolar disorder. The one with the strongest evidence is lithium. It’s particularly effective in preventing relapses and treating bipolar depression and manic episodes. Lithium has also been associated with a decrease in suicides.

Doctors may also prescribe any of the following anticonvulsants:


Effective forms of counseling include psychotherapy, cognitive behavioral therapy, and peer support. Other potential treatments include:

However, more research is needed for these potential treatments.

If you or a loved one receives a diagnosis of any form of bipolar disorder, consider exploring different therapies. Your doctor may recommend combining medication and therapy, too. These treatments together may better manage your symptoms.

Bipolar disorder isn’t well-understood, but we do know that there’s a hereditary connection. If someone in your family has bipolar disorder, your risk of developing the condition is higher than for people without a family history of it. This doesn’t mean that you’ll definitely develop it, though.

If you think you or a loved one may have bipolar disorder, talk to your doctor. They can help you understand your personal risk factors and help determine if you need testing and further evaluation.