Your personality is your own way of thinking, feeling, behaving, and relating to others. Once you become an adult, your personality usually doesn't change much.

Personality disorders are a group of mental disorders. They involve long-term patterns of thoughts and behaviors that are different from what is considered normal in your culture. The thoughts and behaviors are unhealthy and inflexible. They cause serious problems with relationships, work, and social activities. They can make it hard to deal with everyday stresses and problems.

There are 10 types of personality disorders. They are grouped into three different categories called clusters. The types in each cluster have some similar symptoms and characteristics. The clusters and types are:

Cluster A personality disorders involve unusual and odd thoughts and behaviors. It includes:

• Paranoid personality disorder, in which a person has paranoia (an extreme fear and distrust of others). They may think that someone is trying to harm them.
• Schizoid personality disorder, in which a person prefers to be alone and is not interested in having relationships with others.
• Schizotypal personality disorder, in which a person has unusual thoughts and ways of behaving and speaking. They are uncomfortable having close relationships with others.

Cluster B personality disorders involve dramatic and emotional thoughts and behaviors that can keep changing. It includes:

• Antisocial personality disorder, in which a person has a long-term pattern of manipulating, exploiting, or violating the rights of others.
• Borderline personality disorder, in which a person has lots of trouble managing their emotions. This makes them impulsive and uncertain about how they see themselves. It can cause a lot of trouble in their relationships.
• Histrionic personality disorder, in which a person is dramatic, has strong emotions, and always wants attention from others.
• Narcissistic personality disorder, in which a person lacks empathy and wants to be admired by others. They think that they are better than others and that they deserve special treatment.

Cluster C personality disorders involve anxious and fearful thoughts and behaviors. It includes:

• Avoidant personality disorder, in which a person is very shy and feels that they are not as good as others. They often avoid people because they fear rejection.
• Dependent personality disorder, in which a person depends too much on others and feels that they need to be taken care of. They may let others treat them badly because they are afraid of losing the relationship.
• Obsessive-compulsive personality disorder, in which a person needs control and order. They are perfectionists and can be inflexible. Although some of the symptoms are similar, this is not the same thing as obsessive-compulsive disorder (OCD).

Personality disorders usually begin when someone is in their teens or early adult years. The cause is unknown. However, genes and childhood experiences such as abuse and trauma likely play a role.

The symptoms of each personality disorder are different. But each disorder involves problems and uncertainty with how people see themselves. The disorders also cause problems in relationships with other people.

People with personality disorders may have trouble realizing that they have a problem. To them, their thoughts are normal. They may see others as the problem. So they may not seek help when they need it. Or, if they seek help, it may be because of another reason. They may be looking for help because of other mental health symptoms or problems with relationships and work. Sometimes someone else, such as a family member or social agency, may ask them to get help.

A mental health care provider can diagnose personality disorders. A mental health provider is a health care professional who specializes in diagnosing and treating mental health problems. To make a diagnosis, the provider will consider the person's symptoms, experiences, and family medical history. A thorough medical exam may also be done to help rule out other possible causes of the symptoms.

Talk therapy, also known as psychotherapy, is the main treatment for personality disorders. Medicines may help relieve certain symptoms, such as anxiety or mood swings.