Most people have ups and downs in their moods: days when they feel good and others when they feel down. If you have bipolar disorder, your mood swings much further than other people's. Sometimes, you might feel very "high" and have lots of energy. That is called mania. Other times you might feel very low. That is called bipolar depression.

But, in between the mania and the depression, you may have times when you're in a normal, stable mood. That stable mood can last for weeks, months or even years.
Bipolar disorder is also called manic depression and bipolar affective disorder.
- Bipolar disorder is usually something you have for a long time (it is a long-term, or chronic, problem).
- With the right treatment, most people can control their mood swings.
- The time between mood swings varies a lot from person to person.
- How bad the mood swings are also varies a lot between people. They can be mild or severe.
- It often takes several years for your doctors or psychiatrists to realize you have bipolar disorder. And, it can take time for them to work out the best treatment for you.
- If you have bipolar disorder, you will probably need to take drugs for the rest of your life to keep your moods under control.
We don't know exactly how your brain affects your mood. And, we don't know what goes wrong within your brain if you have bipolar disorder. But, doctors and researchers have some ideas.
One idea is that, if you have bipolar disorder, you have problems with the levels of neurotransmitters in your brain. This might cause your mood swings.
People who are depressed have lower levels of certain neurotransmitters than people who are not depressed. For example, they may have lower levels of the ones called dopamine, serotonin and norepinephrine. Treatments to increase levels of serotonin work for depression.1 For more information, see our articles on Depression.
Researchers have found some other differences between the brains of people with bipolar disorder and the brains of other people. But we don't know for certain that these differences cause bipolar disorder. Brain scans show that some people with bipolar disorder have slightly different brains than people without bipolar disorder.
Your hormones can affect your mood. One hormone called adrenaline goes up when you are under stress. This one may especially affect your mood. Your thyroid gland also makes hormones. If your levels of these get too high or too low, it can affect your mood too.
But, we can't say for sure what causes bipolar disorder.
If your doctor has told you that you have bipolar disorder, you will have had at least one bout of very high mood. This is known as mania. Doctors call these bouts manic episodes.
Most people also have at least one bout of very low mood. That is known as depression. When it happens as part of bipolar disorder, it is known as bipolar depression.
People with bipolar disorder have a low mood much more of the time than they have mania.2
There are two basic types of bipolar disorder. They are called bipolar type 1 disorder and bipolar type 2 disorder. Type 1 is more serious.
- Bipolar type 1 disorder means you get bouts of mania and bouts of depression.
- Bipolar type 2 disorder also means you get bouts of mania and bouts of depression. But the mania is milder. It is sometimes called hypomania.
We don't know for sure what causes bipolar disorder. The main thing that seems to mean you are more likely to get it is having a close relative with bipolar disorder. The condition seems to run in families. But not everyone who has close relatives with bipolar disorder gets it themselves.
We know that:1
- If you don't have a relative with bipolar disorder, your chances of getting it are about 1 to 2 in 100
- If you have a close relative (a parent, brother or sister) with bipolar disorder, your chances of getting it are between 5 and 10 in 100
- If you have an identical twin who has bipolar disorder, your chances of getting it are higher than they would be if any other relative had it. If one identical twin has bipolar disorder, the chances of the other twin getting it are between 4 and 7 in 10.
Here are some experiences that can trigger a relapse of bipolar disorder.
- Stressful situations like school exams, problems in your relationships or trouble at work may set off bipolar disorder.
- Sleeping too little or too much can make a relapse of bipolar symptoms more likely. Many doctors advise against partying until late at night, working shifts and other things that might upset your sleep patterns.4
- Illegal drugs and alcohol are often used by people with bipolar disorder. It may be that these drugs bring on the disorder if you are prone to it. Or people may use certain drugs, such as amphetamines (also called speed) or cocaine, to stop feeling the depression from their bipolar disorder.4 So, treatment for bipolar disorder may include treatment for drug problems. Your doctor will always ask if you use drugs as part of diagnosing your condition and checking on your treatment.
- Müller-Oerlinghausen B, Berghöfer A, Bauer M. Bipolar disorder. Lancet. 2002; 359: 241-247. 11812578
- Judd LL, Akiskal HS, Schettler PJ, et al. The long-term natural history of the weekly symptomatic status of bipolar I disorder. Archives of General Psychiatry. 2002; 59: 530-537. 12044195
- Johnstone SG. My bipolar expedition. BMJ. 2006; 332: 30-32. 16399734
- Belmaker RH. Bipolar disorder. New England Journal of Medicine. 2004; 351: 476.
- Terp IM, Mortensen PB. Post-partum psychoses: clinical diagnoses and relative risk of admission after parturition. British Journal of Psychiatry. 1998; 172: 521-526.
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This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment. ©BMJ Publishing Group Limited 2008. All rights reserved. |











