Overview

Onychophagia, commonly known as chronic nail biting, is a body-focused repetitive behavior (BFRB) characterized by the habitual biting of one’s fingernails. It is considered a stress-related or compulsive behavior and is classified under obsessive-compulsive and related disorders in some psychiatric guidelines. Nail biting usually begins in childhood or adolescence and can continue into adulthood if not addressed. While it may seem harmless, persistent onychophagia can lead to physical damage to the nails and surrounding skin, dental issues, and psychological distress.

Causes

The exact cause of onychophagia is multifactorial, involving psychological, behavioral, and sometimes genetic factors. Common causes and triggers include:

• Stress and anxiety: Nail biting often serves as a coping mechanism to relieve stress, nervousness, or anxiety.
• Boredom or inactivity: People may bite their nails during idle moments or when they are bored.
• Perfectionism or frustration: Some individuals bite their nails when they feel dissatisfied or frustrated.
• Habit formation: Repeated nail biting over time can become an automatic, unconscious behavior.
• Genetic predisposition: Onychophagia can run in families, indicating a potential hereditary component.
• Associated mental health conditions: Nail biting may co-occur with attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), or generalized anxiety disorder (GAD).

Symptoms

Onychophagia presents with both physical and psychological symptoms:

• Short, uneven, or damaged nails: The most visible sign of chronic nail biting.
• Redness and soreness: The skin around the nails may appear inflamed or painful.
• Bleeding or infections: Frequent nail biting can lead to skin breaks, increasing the risk of bacterial or fungal infections.
• Dental problems: Nail biting can cause chipped teeth, malocclusion, or jaw strain.
• Gastrointestinal risks: Swallowed nail fragments may cause minor digestive discomfort.
• Embarrassment or shame: Many individuals feel self-conscious about the appearance of their nails.

Diagnosis

Diagnosis of onychophagia is usually clinical, based on the patient’s behavior and physical examination. The steps include:

• Patient history: Healthcare providers inquire about the frequency, triggers, and history of nail biting.
• Physical examination: Inspection of the nails, surrounding skin, and oral cavity for damage or signs of infection.
• Psychological evaluation: Assessment for underlying mental health conditions like anxiety, OCD, or ADHD.
• Diagnostic criteria: In some cases, standardized criteria like the DSM-5 may be used to evaluate compulsive behaviors.

Treatment

There is no single cure for onychophagia, but several behavioral, psychological, and sometimes pharmacological treatments can help:

• Behavioral therapy: Habit reversal training (HRT) is considered the most effective therapy, teaching individuals to recognize triggers and substitute nail biting with healthier actions.
• Cognitive-behavioral therapy (CBT): Addresses underlying stress or anxiety contributing to the habit.
• Bitter-tasting nail polish: Applying aversive coatings discourages nail biting by making the experience unpleasant.
• Stress management techniques: Relaxation exercises, mindfulness, or stress-reduction strategies may reduce the urge to bite nails.
• Medication: In severe cases or when associated with OCD, medications like selective serotonin reuptake inhibitors (SSRIs) may be prescribed.
• Physical barriers: Wearing gloves or adhesive bandages can help prevent access to nails during critical periods.

Prognosis

The prognosis for onychophagia varies based on individual circumstances:

• Favorable outcomes with treatment: Many individuals can significantly reduce or stop nail biting with consistent behavioral interventions.
• Potential for relapse: Stressful situations or emotional triggers may lead to occasional relapses, requiring ongoing coping strategies.
• Early intervention is beneficial: Addressing the behavior in childhood or adolescence tends to have better outcomes than waiting until adulthood.
• Persistent cases: Chronic nail biting without treatment can lead to long-term nail deformities and recurrent infections.

Overall, onychophagia is a manageable condition, and with appropriate behavioral strategies and, when necessary, medical interventions, individuals can achieve healthier habits and improve their nail health.