Self-injury, also known as self-harm, self-mutilation, or self-abuse occurs when someone intentionally and repeatedly harms themselves in a way that is impulsive and not intended to be lethal.
The most common methods are:
- Skin cutting (70-90%),
- Head banging or hitting (21%-44%), and
- Burning (15%-35%).
Other forms of self-injury include excessive scratching to the point of drawing blood, punching self or objects, infecting oneself, inserting objects into body openings, drinking something harmful (like bleach or detergent), and breaking bones purposefully.  Most individuals who engage in non-suicidal self-injury (NSSI) hurt themselves in more than one way.
Research indicates that self-injury occurs in approximately as many as 4% of adults in the United States. Rates are higher among adolescents, who seem to be at an increased risk for self-injury, with approximately 15% of teens reporting some form of self-injury. Studies show an even higher risk for self-injury among college students, with rates ranging from 17%-35%. 
People who self-injure commonly report they feel empty inside, over or under stimulated, unable to express their feelings, lonely, not understood by others and fearful of intimate relationships and adult responsibilities. Self-injury is their way to cope with or relieve painful or hard-to-express feelings, and is generally not a suicide attempt. But relief is temporary, and a self-destructive cycle often develops without proper treatment.Self-inury can also be a way to have control over your body when you can’t control anything else in your life. A lot of people who cut themselves also have an eating disorder.
By engaging in self-injury, a person intends to:
- Obtain relief from a negative feeling or mental state
- Resolve an interpersonal difficulty, like a disagreement with a friend or loved one
- Deal with an intrapersonal problem, like boredom
- Induce a positive feeling state 
Warning signs that someone may be injuring themselves include:
- Unexplained frequent injuries including cuts and burns,
- Low self-esteem,
- Difficulty handling feelings,
- Relationship problems or avoidance of relationships, and
- Poor functioning at work, school or home.
People who self-injure may attempt to conceal their marks, such as bruises, scabs or scars with clothing, and you may notice them wearing inappropriate clothing like long sleeves and pants in hot weather. If discovered, a person who self-injures may often make excuses as to how an injury happened (for instance, “I fell” or “The cat scratched me”).
The diagnosis for someone who self-injures can only be determined by a licensed psychiatric professional. Self-injury behaviors can be a symptom other mental illnesses such as: personality disorders (esp. borderline personality disorder); bipolar disorder (manic depression); major depression; anxiety disorders (esp. obsessive-compulsive disorder); and psychotic disorders such as schizophrenia.
Criteria for a Diagnosis of Non-Suicidal Self-Injury 
- Intentional self-inflicted damage to the surface of the body with expectation of physical harm, but without suicidal intent for 5 or more days within the past year;
- Person injures themself for at least one of the following reasons:
- To seek relief from negative thoughts or feelings
- To resolve an interpersonal difficulty, or
- To bring about positive feelings.
- Before the behavior, a person experiences one of the following:
- Interpersonal difficulty or negative feelings and thoughts (including depression, anxiety),
- Preoccupation about self-injury that is hard to resist
- Frequent urges to self injure
- The behavior is not accepted by society (body piercing,tattooing, scab picking and nail biting do not qualify for the diagnosis)
- The person is significantly distressed by the behavior
- The behavior can’t be explained by another mental, developmental or other medical condition.
The relationship between suicide and self-injury is complicated. While people with non-suicidal self injury do not intend to completed suicide, they may cause more harm than intended, which could result in medical complications or death. In severe or prolonged cases of self-injury, a person may become desperate about their lack of control over the behavior and its addictive nature, which may lead them to true suicide attempts.
If someone displays the signs and symptoms of self-injury, a mental health professional with self-injury expertise should be consulted. An evaluation or assessment is the first step, followed by a recommended course of treatment to prevent the self-destructive cycle from continuing.
Self-injury treatment options include outpatient therapy, partial-inpatient (6-12 hours a day) and inpatient hospitalization. When the behaviors interfere with daily living, such as employment and relationships, and are health or life-threatening, a specialized self-injury hospital program with an experienced staff is recommended.
Effective treatment of self-injury is most often a combination of medication, cognitive/behavioral therapy, and interpersonal therapy, supplemented by other treatment services as needed.
- Medication is often useful in the management of depression, anxiety, obsessive-compulsive behaviors, and the racing thoughts that may accompany self-injury.
- Cognitive/behavioral therapy helps individuals understand and manage their destructive thoughts and behaviors. Contracts, journals, and behavior logs are useful tools for regaining self-control.
- Interpersonal therapy assists individuals in gaining insight and skills for the development and maintenance of relationships.
Services for eating disorders, alcohol/substance abuse, trauma, abuse, and family therapy should be readily available and integrated into treatment, depending on individual needs.
Successful courses of treatment are marked by:
- An individual's active involvement and committment to their treatment,
- Aftercare plans with support for the individual's new self-management skills and behaviors, and
- Collaboration between all involved professionals (medical and otherwise).