An<unk>  is a disease made up by doctors, often a diagnostic trend or fad that has become or is expected to become obsolete or discredited.
Examples of diseases considered or accused of being<unk> s include nymphomania, hystero-epilepsy, repressed memory, autogynephilia, and multiple personality disorder.
In many cases, it has been shown that "experts" who believe in the disease are able to observe or even induce symptoms matching the disease's description in suggestible patients. In the case of hystero-epilepsy, it was shown that moving those allegedly afflicted with the disease into different settings made their symptoms disappear.
The concept of<unk>  has important implications for those who diagnose "diseases" of behavior.
Iatrogenic artifact
Cognitive bias
Biological hazard
Mass effect 
Congenital abnormality
Medical underwriting
Lotus effect
Drug interaction