While it is a disorder that affects an estimated 2 percent of the world’s population, bipolar disorder is one of the most difficult diseases for those who don’t suffer from it to understand.

Marked by soaring highs and crushing lows, the disorder causes sometimes wild spikes in energy and activity levels, making it difficult to carry out everyday activities.

The disorder is so widespread, that World Bipolar Day, a day set aside to raise awareness of the disorder and erase the stigmatism of mental illness, is observed in September. The observance falls on the anniversary of the birth of Vincent Van Gogh. It is believed the famous painter suffered from the disorder.

Here’s a look at bipolar disorder, the symptoms and where you can get help.

What is it?

Bipolar disorder is a psychological disorder characterized by “manic” episodes, either preceding or following a time of a major  depression. Manic episodes are defined as experiencing a period of at least 1 week where you have “an elevated, expansive or unusually irritable mood, as well as notably persistent goal-directed activity,” according to psychcentral.com.

What are the types of bipolar disorder?

WebMD describes the types of bipolar disorders this way:  

Bipolar I

A person affected by bipolar I disorder has had at least one manic episode in his or her life. A manic episode is a period of abnormally elevated mood, accompanied by abnormal behavior that disrupts life.

Bipolar II

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-on mania.

Rapid Cycling

In rapid cycling, a person with bipolar disorder experiences four or more episodes of mania or depression in one year. About 10 percent to 20 percent of people with bipolar disorder have rapid cycling.

Mixed Bipolar

In most forms of bipolar disorder, moods alternate between elevated and depressed over time. But with mixed bipolar disorder, a person experiences both mania and depression simultaneously or in rapid sequence.

Cyclothymia

Cyclothymia (cyclothymic disorder) is a relatively mild mood disorder. People with cyclothymic disorder have milder symptoms than in full-blown bipolar disorder.

What are the symptoms?

According to the National Institute of Mental Health, here are the symptoms of bipolar disorder.  

The depression phase

Symptoms of a depressive episode may include:

• No interest in activities you once enjoyed

• Loss of energy

• Difficulty sleeping—either sleeping too much or not at all

• Changes in appetite—eating too much or too little

• Difficulty concentrating, remembering, or making decisions

• Thoughts of death or suicide

The manic phase

Symptoms of a manic episode may include:

• Feelings of euphoria, abnormal excitement, or elevated mood

• Talking very rapidly or excessively

• Needing less sleep than normal, yet still having plenty of energy

• Feeling agitated, irritable, hyper, or easily distracted

• Engaging in risky behavior such as lavish spending, impulsive sexual encounters, or ill-advised business decision

What resources are available?

Click here for a link to resources for patients via the International Society for Bipolar Disorders.

When to get emergency help

Suicidal thoughts and behavior are common among people with bipolar disorder. If you think you may hurt yourself and need help, call 911, or the National Suicide Prevention Lifeline at 800-273-TALK (800-273-8255) to reach a trained counselor.

Use that same number and press 1 to reach the Veterans Crisis Line.