May also be called: Manic Depression; Manic-Depressive Disorder; Manic-Depressive Illness; Bipolar Mood Disorder; Bipolar Affective Disorder Bipolar disorder is a type of mood disturbance characterized by episodes of low-energy depression (symptoms include sadness, fatigue, and hopelessness) and high-energy mania (signs include increased energy, sleep loss, and reckless behavior). More to Know Bipolar disorder is a type of depressive disorder, a medical condition that affects the way a person's brain functions. Someone with bipolar disorder will go through episodes of mania and at other times experience episodes of depression. Doctors aren't sure exactly what causes bipolar disorder, but they believe it's linked to imbalances in certain brain chemicals called neurotransmitters. If the neurotransmitters aren't in balance, the brain's mood-regulating system won't work the way it should. Often, episodes of mania or depression last for weeks or months, but they can change rapidly, even during the course of a day. During manic episodes, a person with bipolar disorder may have increased energy and activity, an elevated mood, racing thoughts, difficulty concentrating, and less need for sleep. He or she may also exhibit poor judgment and engage in reckless or aggressive behavior. Periods of depression are marked by a loss of energy, prolonged sadness, feelings of guilt or worthlessness, sleeping and eating problems, and thoughts of death or suicide. Treatment for bipolar disorder typically involves the use of medications, such as mood stabilizers, along with counseling or psychotherapy. Keep in Mind There's no cure for bipolar disorder, but most people who have it can be helped if a psychiatrist or psychologist diagnoses the disorder. Without treatment, bipolar disorder can get worse, but by following a treatment plan and making a few lifestyle changes — such as reducing stress, eating well, and getting enough sleep and exercise — people living with bipolar disorder can usually control their symptoms and lead normal lives. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles Word! Depression It's normal to feel sad sometimes, but if you feel that way for a long time, and you never feel happy, it's called depression. Read More Taking Your Child to a Therapist Many children and teens have problems that affect how they feel, act, or learn. Going to therapy helps them cope better, feel better, and do better. Read More Stress & Coping Center Visit our stress and coping center for advice on how to handle stress, including different stressful situations. Read More When Depression Is Severe Severe depression can cloud a person's thinking and lead some people to think that life isn't worth living. But severe depression can be treated. Find out what to do and how to get help in this article for teens. Read More Why Do People Get Depressed? There's no one reason why people get depressed - many different things can play a role. Find out more about the things that can trigger depression. Read More Finding Low-Cost Mental Health Care If you need mental health care but don't think you can afford it, you're not alone. Get tips on finding low-cost or free mental health care in this article for teens. Read More Sadness and Depression Everyone is sad once in a while. But depression is a sadness that goes on too long and hurts too much. Find out more in this article for kids. Read More Depression Depression is very common. For more information about depression and feeling better, check out this article. Read More Depression Depression is the most common mental health disorder in the U.S. If you think your child is depressed, you'll want to learn more about what depression is, what causes it, and what you can do to help. Read More 5 Ways to Help Yourself Through Depression It's important to take action against depression - it doesn't just go away on its own. In addition to getting professional help, here are 5 ways to feel better. Read More Talking to Parents About Depression If you feel depressed, you need to reach out for help and support. Read our tips for teens on talking to parents about depression. Read More Bipolar Disorder Bipolar disorders are one of several medical conditions called depressive disorders that affect the way a person's brain functions. Find out more about bipolar disorder. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.