Factitious disorder symptoms involve mimicking or producing illness or injury. People go to great lengths to avoid discovery of their deception, so it may be difficult to realize that their symptoms are actually part of a serious mental disorder.

Factitious disorder imposed on another (previously called Munchausen syndrome by) is when someone makes another person sick, requiring medical attention. Usually this involves a parent harming a child. This form of child abuse can put a child in serious danger of injury or unnecessary medical care.

Factitious disorder signs and symptoms may include:

Clever and convincing medical problems
Frequent hospitalizations
Vague or inconsistent symptoms
Conditions that get worse for no apparent reason
Conditions that don't respond as expected therapies
Eagerness to have frequent testing or risky operations
Extensive knowledge of medical terms and diseases
Seeking treatment from many different doctors or hospitals, which may include using a fake name
Having few visitors when hospitalized
Reluctance to allow health professionals to talk to family or friends or to other health care providers
Arguing with hospital staff
Frequent requests for pain relievers or other medications
How those with factitious disorder fake illness

Because people with factitious disorder become experts at faking symptoms and diseases or inflicting real injuries upon themselves, it may be hard for medical professionals and loved ones to know if illnesses are real or not.