Dermatophagia is a form of obsessive-compulsive disorder

Obsessive-compulsive disorder

Obsessive–compulsive disorder is an anxiety disorder characterized by intrusive thoughts that produce uneasiness, apprehension, fear, or worry, by repetitive behaviors aimed at reducing the associated anxiety, or by a combination of such obsessions and compulsions...

 wherein a sufferer compulsively bites their own skin. Sufferers typically bite the skin around the nails, leading to bleeding and discoloration over time.

Behavior

Dermatophagia sufferers chew their skin out of compulsion, and can do so on a variety of places on their body. Sufferers typically chew the skin surrounding their fingernails and joints. They could also chew on the inside of their mouth, cheeks, and/or lips, causing blisters in and outside of the mouth. If the behavior is left unchecked for an extended period, calluses may start to develop where most of the biting is done.

Skin chewing can be bolstered by times of apprehension and other unpleasant events. Blister

Blister

A blister is a small pocket of fluid within the upper layers of the skin, typically caused by forceful rubbing , burning, freezing, chemical exposure or infection. Most blisters are filled with a clear fluid called serum or plasma...

s in particular can cause a feeling of desire to pull or bite off the affected skin (since the skin is dead, thus easily pulled off), which could be detrimental, causing infection

Infection

An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...

. Another disorder, known as dermatillomania

Dermatillomania

Dermatillomania is an impulse control disorder characterized by the repeated urge to pick at one's own skin, often to the extent that damage is caused...

, the act of picking at one's skin, can sometimes accompany dermatophagia.

Dermatophagia can be considered a "sister" disorder to Trichophagia

Trichophagia

Trichophagia is the compulsive eating of hair associated with trichotillomania . In trichophagia, people with trichotillomania also ingest the hair that they pull; in extreme cases this can lead to a hair ball ....

, which involves compulsively biting and eating one's hair.

See also

• Body-focused repetitive behavior
  Body-focused repetitive behavior
  Body-Focused Repetitive Behavior is an umbrella name for impulse control behaviors involving compulsively damaging one's physical appearance or causing physical injury.The main BFRB disorders are:*Trichotillomania, compulsive hair pulling...
  
  
• Dermatillomania
  Dermatillomania
  Dermatillomania is an impulse control disorder characterized by the repeated urge to pick at one's own skin, often to the extent that damage is caused...
  
  
• Nail biting
  Nail biting
  Onychophagia, or nail biting, is a common oral compulsive habit in children and adults.-Classification:Nail biting is considered an impulse control disorder in the DSM-IV-R; the ICD-10 classifies it as "other specified behavioral and emotional disorders with onset usually occurring in childhood and...
  
  
• Trichotillomania
  Trichotillomania
  Trichotillomania, which is classified as an impulse control disorder by DSM-IV, is the compulsive urge to pull out one's own hair leading to noticeable hair loss, distress, and social or functional impairment. It is often chronic and difficult to treat....
  
  
• Lesch-Nyhan Syndrome
  Lesch-Nyhan syndrome
  Lesch–Nyhan syndrome , also known as Nyhan's syndrome, Kelley-Seegmiller syndrome and Juvenile gout, is a rare inherited disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase , produced by mutations in the HPRT gene located on X chromosome. LNS affects about...