Signs and symptoms of self-injury may include:

• Scars, often in patterns
• Fresh cuts, scratches, bruises, bite marks or other wounds
• Excessive rubbing of an area to create a burn
• Keeping sharp objects on hand
• Wearing long sleeves or long pants, even in hot weather
• Frequent reports of accidental injury
• Difficulties in interpersonal relationships
• Behavioral and emotional instability, impulsivity and unpredictability
• Statements of helplessness, hopelessness or worthlessness

Forms of self-injury

Self-injury usually occurs in private and is done in a controlled or ritualistic manner that often leaves a pattern on the skin. Examples of self-harm include:

• Cutting (cuts or severe scratches with a sharp object)
• Scratching
• Burning (with lit matches, cigarettes or heated, sharp objects such as knives)
• Carving words or symbols on the skin
• Self-hitting, punching or head banging
• Piercing the skin with sharp objects
• Inserting objects under the skin

Most frequently, the arms, legs and front of the torso are the targets of self-injury, but any area of the body may be used for self-injury. People who self-injure may use more than one method to harm themselves.

Becoming upset can trigger an urge to self-injure. Many people self-injure only a few times and then stop. But for others, self-injury can become a long-term, repetitive behavior.

There's no one single or simple cause that leads someone to self-injure. In general, self-injury may result from:

• Poor coping skills. Nonsuicidal self-injury is usually the result of an inability to cope in healthy ways with psychological pain.
• Difficulty managing emotions. The person has a hard time regulating, expressing or understanding emotions. The mix of emotions that triggers self-injury is complex. For instance, there may be feelings of worthlessness, loneliness, panic, anger, guilt, rejection, self-hatred or confused sexuality

Through self-injury, the person may be trying to:

• Manage or reduce severe distress or anxiety and provide a sense of relief
• Provide a distraction from painful emotions through physical pain
• Feel a sense of control over his or her body, feelings, or life situations
• Feel something — anything — even if it's physical pain, when feeling emotionally empty
• Express internal feelings in an external way
• Communicate depression or distressful feelings to the outside world
• Be punished for perceived faults

Most people who self-injure are teenagers and young adults, although those in other age groups also self-injure. Self-injury often starts in the preteen or early teen years, when emotions are more volatile and teens face increasing peer pressure, loneliness, and conflicts with parents or other authority figures.

Certain factors may increase the risk of self-injury, including:

• Having friends who self-injure. People who have friends who intentionally harm themselves are more likely to begin self-injuring.
• Life issues. Some people who injure themselves were neglected, were sexually, physically or emotionally abused, or experienced other traumatic events. They may have grown up and still remain in an unstable family environment, or they may be young people questioning their personal identity or sexuality. Some people who self-injure are socially isolated.
• Mental health issues. People who self-injure are more likely to be highly self-critical and be poor problem-solvers. In addition, self-injury is commonly associated with certain mental disorders, such as borderline personality disorder, depression, anxiety disorders, post-traumatic stress disorder and eating disorders.
• Alcohol or drug use. People who harm themselves often do so while under the influence of alcohol or recreational drugs.

Self-injury can cause a variety of complications, including:

• Worsening feelings of shame, guilt and low self-esteem
• Infection, either from wounds or from sharing tools
• Permanent scars or disfigurement
• Severe, possibly fatal injury
• Worsening of underlying issues and disorders, if not adequately treated

Suicide risk

Although self-injury is not usually a suicide attempt, it can increase the risk of suicide because of the emotional problems that trigger self-injury. And the pattern of damaging the body in times of distress can make suicide more likely.