Nail biting, also known as onychophagy or onychophagia, is an oral compulsive habit of biting one’s fingernails. It is sometimes described as a parafunctional activity, the common use of the mouth for an activity other than speaking, eating, or drinking. Nail biting is very common, especially amongst children.


Cluster Number:
Wiki Number: PW142
Diagnosis: Onchyophagia-(Nail-Biting)
US Patients:
World Patients:
Sex Ratio:
Age Onset: 30% of children, 45% of teenagers
Brain Area:
Symptoms: an oral compulsive habit, considered an impulse-control disorder
Progression: broken skin on the cuticles can infect; saliva may infect the skin, damage to teeth from the biting, and stomach from swallowing
Causes: parents with mental disorders may be a risk-factor
Medications: applying a bitter nail polish, denatonium benzoate, may solve the problem
Therapies: Parental punishments may increase nail-biting. But other counseling programs may help.


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