Bipolar Disorder - Causes

The cause of bipolar disorder has not yet been discovered. Many researchers believe that heredity is an important factor. Two-thirds of bipolar patients have a family history of mental disorders. Some research studies claim to have found a genetic link for bipolar disorder. Genes are the chemical units present in all cells that tell cells what functions to perform. Genes are passed down from parents to children.

Some researchers also believe that abnormal levels of certain chemicals in the body can cause bipolar disorder. For example, some studies have shown that people with bipolar disorder have abnormal levels of dopamine in their brains. Dopamine is a neurotransmitter, a chemical that carries messages in the brain.

Drug abuse may be associated with bipolar disorder also. Up to 30 percent of those who abuse cocaine also have bipolar disorder. Researchers are not sure about this connection, however. It may be that bipolar disorder leads to drug abuse, or that drug abuse leads to bipolar disorder. Or it may be that both conditions are caused by some abnormal condition in a person's body.

Bipolar disorder has also been shown to be associated with the seasons. Some patients experience mania during the summer months and depression during the winter months.