Dissociative identity disorder, previously known as multiple personality disorder, is a type of dissociative disorder. Along with dissociative amnesia and depersonalization-derealization disorder, it’s one of the three major dissociative disorders.

Dissociative disorders can be found in people of all ages, races, ethnicities, and backgrounds. The National Alliance on Mental Illness (NAMI) estimates that about 2 percent of people experience dissociative disorders.

The most recognizable symptom of dissociative identity disorder (DID) is a person’s identity being involuntarily split between at least two distinct identities (personality states). Other symptoms might include:

  • Dissociative amnesia. This is a type of memory loss — beyond forgetfulness — that’s not associated with a medical condition.
  • Dissociative fugue. A dissociative fugue is an episode of amnesia that involves not having memory of certain personal information. It may include wandering off or a detachment from emotion.
  • Blurred identity. This occurs when you feel like there are two or more people talking or living in your head. You might even feel like you’re possessed by one of several other identities.

It’s important to note that according to the Diagnostic and Statistical Manual of Mental Disorders, many cultures around the globe include possession as part of a normal spiritual ritual or practice. This isn’t considered a dissociative disorder.

Interacting with someone with dissociative identity disorder

If you believe someone you know has DID, you may get the impression that you’re communicating with not one, but several different people, as the person switches between personalities.

Often, each identity will have their own name and characteristics. They’ll each commonly have an unrelated detailed background with obvious differences in age, gender, voice, and mannerisms. Some might even have individual physical characteristics such as a limp or poor vision that requires glasses.

There are often differences in each identity’s awareness and relationship — or lack thereof — to the other identities.

Dissociative identity disorder — along with other dissociative disorders — usually develop as a way to deal with some type of trauma they’ve experienced.

According to the American Psychiatric Association, 90 percent of people with dissociative identity disorder in the United States, Canada, and Europe have experienced childhood neglect or abuse.

The primary treatment for DID is psychotherapy. Also known as talk therapy or psychosocial therapy, psychotherapy is focused on talking with a mental health professional about your mental health.

The goal of psychotherapy is to learn how to cope with your disorder and to understand the cause of it.

Hypnosis is also considered by some to be a useful tool for DID treatment.

Medication is sometimes used in the treatment of DID, as well. Although there are no medications specifically recommended for the treatment of dissociative disorders, your doctor might use them for associated mental health symptoms.

Some commonly used medications are:

If you can identify with any of the following, you should make an appointment to see your doctor:

  • You are aware — or others observe — that you involuntarily and unwillingly have two or more personalities or identities that have a distinctly different way of relating to you and the world around you.
  • You experience beyond ordinary forgetfulness, like extensive gaps in your memory for important personal information, skills, and events.
  • Your symptoms aren’t caused by a medical condition or from the use of alcohol or drugs.
  • Your symptoms are causing you problems or stress in important areas such as your personal life and at work.

If you identify with the symptoms of dissociative identity disorder, you should make an appointment to see your doctor.

If your friend or a loved one is displaying the common symptoms, you should encourage them to seek help. You can also contact the NAMI HelpLine at 1-800-950-6264 or email info@nami.org for support.