Factitious disorder, which was previously called Munchausen syndrome, is a mental illness characterized by faking illness or purposely becoming ill or injured. It may take the form of self-harm and injury or faking one’s own illness. The disorder also may involve hurting someone else or presenting another person as being sick or injured when they are not. Factitious disorder can range from mild to severe, from exaggerating illness to completely faking an illness or intentionally causing harm.

This is a difficult mental disorder to identify and treat. Someone with factitious disorder wants to be in the role of patient or of being sick, or wants to have someone else, often a child, be in that role. The motives and the reasons for this are challenging to understand.

Treatment typically includes medical care and therapy. Medications may be helpful, and in some cases an individual may need to be hospitalized. Treatment can be difficult because it requires that the patient recognize they have the condition. Without this acceptance the prognosis is not always good, but treatment is worth trying because the complications of factitious disorder can be serious and may include real physical harm.

There are two main types of factitious disorder, based on whether the person with the condition is faking or causing his or her own illness or injury or is doing it to someone else.

• Factitious disorder imposed on self. This type of factitious disorder, which used to be called Munchausen syndrome, occurs when someone fakes psychological or physical symptoms of an illness, disorder, or injury. In some cases the individual may purposely get sick or cause their own injury or harm.
• Factitious disorder imposed on another. Previously called Munchausen by proxy, this form of factitious disorder occurs when someone fakes or imposes injury or illness on someone else. The other person is usually someone in the person’s care, such as a child, an elderly relative, or a disabled individual. It may also be a pet. The most common form of this type of the disorder is a mother faking illness or causing illness in a child.

Factitious disorder can also be categorized by the type of illness faked or triggered. Some people fake psychological symptoms, while others fake or cause physical symptoms. Some people with the disorder may include a combination of both.

There are not many statistics available for factitious disorder, as it has been studied less than other mental illnesses and because patients often don’t admit to having the condition. This makes it difficult to collect information about factitious disorder.

• It is thought that about one percent of people admitted to hospitals are diagnosed with factitious disorder, but it is probably under-reported.
• One study of patients in a psychiatric hospital found that eight percent showed some symptoms of factitious disorder.
• Another study reviewed papers to determine statistical information about factitious disorder. From a sample of 455 diagnosed patients they found that 66 percent were female.
• The mean age of the patients in the study was 34.
• More than half of the patients, 58.7 percent, chose to actually cause themselves harm rather than to only fake illness or injury.

Diagnosis of factitious disorder is very difficult. One reason is that a person with this condition is good at faking symptoms and illness. They may use multiple doctors, fake names, and rely on privacy rules to make collecting medical records difficult. Another reason this mental illness is challenging to diagnose is that people with factitious disorder are unlikely to admit to or even be able to recognize their own flawed thinking and behaviors. In other words, they don’t think there is anything wrong with them.

To make a diagnosis, a doctor or psychiatrist should be able to access medical records, but there other ways they can get the necessary information: an interview with the patient, interviews with close family members, the criteria for factitious disorder from The Diagnostic and Statistical Manual of Mental Disorders, as well as medical tests.

The first professional to suspect factitious disorder is usually a physician treating a patient for something that seems to be self-imposed or fake. Some signs that may make a doctor take note and suspect factitious disorder include:

• An illness that does not follow the expected course
• A medical history and present observations inconsistent with each other
• Multiple admissions to different hospitals or visits with several doctors on the medical record
• Textbook knowledge of illnesses
• Failure to find evidence of a patient’s complaint, such as no dehydration when a patient complains of constant diarrhea
• Appropriate treatments don’t improve symptoms
• Signs of self-injury
• Multiple surgical scars
• New symptoms after diagnostic tests come back negative
• Catching a patient lying about symptoms or medical history, or even tampering with medical equipment or records

The symptoms of factitious disorder imposed on another may be similar, but the supposed or imposed illness or injury is observed in another person. Some of the common medical presentations seen in the victim include:

• Poisoning
• Bleeding
• Seizures
• Depression of the central nervous system
• Diarrhea or vomiting
• Fever
• Skin rashes
• High or low blood sugar
• Apnea

Some other signs of factitious disorder imposed on another include multiple or recurrent illnesses in the victim, a perpetrator who is extremely attentive to the victim but who is less worried than medical professionals, a child or other victim who resists treatment, and discrepancies between the victim’s medical records, medical tests, symptoms, and general health.