Onychophagia: Compulsive Nail Biting

What Is Compulsive Nail Biting?

Compulsive nail biting is a body focused repetitive behavior that results in the destruction of one's own fingernails and often the skin around the nails and cuticles. Nail-biting is fairly common, but for some it is more than just a bad habit. It can become quite serious, as people who suffer from compulsive nail-biting may experience bleeding, bruises, infections, or even permanent damage to the fingers. The behavior is often unconscious, and people with this compulsion may have difficulty stopping because they may be unaware of their actions. Compulsive Nail Biting is also called onychophagia. Compulsively biting just the skin is called dermatophagia. Theses behaviors are classified by psychiatrists as a type of impulse control disorder.

What Causes Compulsive Nail Biting?

The cause of compulsive nail biting is probably a combination of biological and environmental factors. Many animals engage in excessive skin picking and scratching, and some have theorized that an out-of-control grooming mechanism in the brain causes these behaviors. Scientists have developed mice who are missing a certain gene, causing them to engage in compulsive grooming that leads to bald spots and patches of missing fur. These behaviors may increase when under stress.

Compulsive nail biting is often observed in people suffering from obsessive-compulsive disorder and body dysmorphic disorder. The most well-understood form of compulsive self-mutilation is trichotillomania or hair pulling, and this also tends to disproportionately afflict people with OCD. Because it is a repetitive behavior and common in people with obsessive-compulsive disorder, is sometimes considered a related OC spectrum disorder. These disorders tend to run in families.

There are several reasons why nail-biters continue their behaviors, and it can be more that just a matter of will-power.

  • Self-Soothing: When stressed, many people feel a need for self-soothing and find they feel better when they bite their nails. It has a sort of calming effect on their nervous systems and reduces levels of stimulation.
  • Stimulation: On the other hand, when people are bored or inactive, nail-biting may provide a needed level of stimulation for the nervous system. It may help keep a person alert or awake when they would otherwise become bored or distracted.
  • Perfectionism: Nail-biters may spend hours examining their nails or fingers for the tiniest irregularity and then try to fix it, in hopes of achieving an improved appearance. Paradoxically, the nail-biting always ends up with the nails looking much worse in spite of their efforts.

Nail-biting can result in a self-perpetuating cycle. Nail-biting may lead to shame and anxiety, which can result in more of the behavior.

Treatment for Compulsive Nail Biting

The Terminology of
Repetitive Self-Mutilation

The most common behaviors performed by people suffering from superficial compulsive self-mutilation are not dangerous but can become extreme. These include hair-pulling, nail-biting, and the picking and scratching of scabs and skin.

  • Hair Pulling: trichotillomania
  • Skin Picking: dermatillomania
  • Nail Biting: onychophagia

These three behaviors are probably all different aspects of the same problem.

Though it may be hard to imagine, nail-biting can become a major focus of life and can interfere with relationships, work, and general happiness. Not recognizing the problem as a real disorder, many do not seek treatment. People with compulsive nail-biting may feel crazy and out of control, but not know what to do or where to go for help. Fortunately, nail-biting responds fairly well to medication and behavioral therapy.

Medication: The medications mainly used to treat nail-biting are the same group as those used for OCD, including antidepressants (SSRIs). Drugs that help nail-biting may take several weeks before they start working. They also may not work perfectly. Usually, 65 percent improvement from a medication is considered a good result. Medication should never be considered an end in itself, but a tool to help with therapy.

Psychotherapy: Cognitive-behavior therapy has been studied as a means of treating nail-biting and related disorders. Therapy may involve several different techniques, outlined below:

  • Habit Reversal Training (HRT) is a four-step process which teaches the person with how to relax, how to breathe and feel centered, and to perform muscle response exercises. HRT includes self-monitoring and stimulus control (described below) and social support.

  • Self-Monitoring is simply making the nail-biter more aware of their behaviors. As the behavior can often be unconscious, awareness can be improved by simply keeping a log of picking behaviors. The very act of recording the behavior can also interrupt the process and reduce the picking.

  • Stimulus Control (SC) is a behavioral treatment that helps sufferers identify and eliminate, avoid, or change the environmental factors, moods, or circumstances that trigger nail-biting. The goal is to consciously control these triggers to create new learned connections between the urges and alternative, non-destructive behaviors. For example if nail-biting usually occurs while alone, the person will be encouraged to spend more time with others. If nail-biting occurs at home while reading, then the person may be asked to wear gloves during this time.

  • Competing Response is a technique designed to give the person an alternative to nail-biting. This can include fidget toys, knitting, beading, or other activities to keep the hands busy. Chewing gum, toothpicks, and other orally-oriented behaviors may be also used to satisfy the urge to chew.

These techniques are all temporary means of helping the person learn to resist the urge to bite and pick at the nails. The more the urge is resisted, over time the weaker the urge becomes. Once the urge fades, these techniques become less necessary. The length of time it takes to extinguish the behavior depends on how long the person has had the problem and how diligent they are in resisting the urges. Although therapy typically lasts from 10-12 weeks, it can take up to 12 months for the urge to pick to finally fade away.

Read about How to Stop Nail and Cuticle Biting

Return to OC Spectrum Disorders...

Credits: Article written by M. Williams, Ph.D.

Disclaimer: This information should not be considered medical advice and should not substitute the judgment of a competent psychiatrist.

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Obsessive-Compulsive Disorder
Tourette Syndrome
Body Dysmorphic Disorder
Depersonalization Disorder
Trichotillomania (Hair Pulling)
Compulsive Skin Picking
Nail Biting
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