Munchausen Syndrome by Proxy

Medically Reviewed by Smitha Bhandari, MD on August 25, 2022
Written by WebMD Editorial Contributors
4 min read

Munchausen syndrome by proxy (MSP) -- or Munchausen by proxy -- is a psychological disorder marked by attention-seeking behavior by a caregiver through those who are in their care.

MSP is a relatively rare behavioral disorder. It affects a primary caretaker, often the mother. The person with MSP gains attention by seeking medical help for exaggerated or made-up symptoms of a child in their care. As health care providers strive to identify what's causing the child's symptoms, the deliberate actions of the parent or caretaker can often make the symptoms worse.

The person with MSP does not seem to be motivated by a desire for any type of material gain. While health care providers are often unable to identify the specific cause of the child's illness, they may not suspect the parent or caretaker of doing anything to harm the child. In fact the caregiver often appears to be very loving and caring and extremely distraught over their child's illness.

People with MSP may create or exaggerate a child's symptoms in several ways. They may simply lie about symptoms, alter tests (such as contaminating a urine sample), falsify medical records, or they may actually induce symptoms through various means, such as poisoning, suffocating, starving, and causing infection.

Certain characteristics are common in a person with MSP, including:

  • Is a parent or caregiver, usually a mother
  • May be a health care professional
  • Is very friendly and cooperative with the health care providers
  • Appears quite concerned (some may seem overly concerned) about their child
  • May suffer from Munchausen syndrome (a related disorder in which a person repeatedly acts as if they have a physical or mental illness when they are not really sick)

Other possible warning signs of MSP include:

  • The child has a history of many hospitalizations, often with a strange set of symptoms.
  • Worsening of the child's symptoms generally is reported by the parent and is not witnessed by the hospital staff.
  • The child's reported condition and symptoms do not agree with the results of tests.
  • There may be more than one unusual illness or death of children in the family.
  • The child's condition improves in the hospital, but symptoms recur when the child returns home.
  • Blood in lab samples may not match the blood of the child.
  • There may be signs of chemicals in the child's blood, stool, or urine.

The exact cause of MSP is not known, but researchers are looking at the roles of biological and psychological factors in its development. Some theories suggest that a history of abuse or neglect as a child, or the early loss of a parent may be factors in its development. Some evidence suggests that major stress, such as marital problems, can trigger MSP.

There are no reliable statistics regarding the number of people in the U.S. who suffer from MSP, and it is difficult to assess how common the disorder is because many cases go undetected.

Diagnosing MSP is very difficult because of the dishonesty that is involved. Doctors must rule out any possible physical illness as the cause of the child's symptoms before a diagnosis of MSP can be made.

If a physical cause of the symptoms is not found, a thorough review of the child's medical history, as well as a review of the family history and the parent's medical history (many have Munchausen syndrome themselves) may provide clues to suggest MSP. Remember, it is the adult, not the child, who is diagnosed with MSP.

The first concern in MSP is to ensure the safety and protection of any real or potential victims. This may require that the child be placed in the care of another. In fact, managing a case involving MSP often requires a team that includes a social worker, foster care organizations, and law enforcement, as well as doctors.

Successful treatment of people with MSP is difficult because those with the disorder often deny there is a problem. In addition, treatment success is dependent on the person telling the truth, and people with MSP tend to be such accomplished liars that they begin to have trouble telling fact from fiction.

Psychotherapy (a type of counseling) generally focuses on changing the thinking and behavior of the individual with the disorder (cognitive-behavioral therapy). The goal of therapy for MSP is to help the person identify the thoughts and feelings that are contributing to the behavior, and to learn to form relationships that are not associated with being ill.

This disorder can lead to serious short- and long-term complications, including continued abuse, multiple hospitalizations, and the death of the victim. (Research suggests that the death rate for victims of MSP is about 10%.) In some situations, a child victim of MSP learns to relate getting attention to being sick and develops Munchausen syndrome themselves.

In general, MSP is a very difficult disorder to treat and often requires years of therapy and support.

In addition, MSP is considered a form of child abuse, which is a criminal offense.

There is no known way to prevent this disorder.