A wide range of poisonings and injuries are included in deliberate self-harm (DSH), which is a significant health problem in some communities. After rising for several years, incidence rates for DSH have declined in the past decade, especially among men 15 to 34 years of age. The rate has remained stable among women. Although most patients initially present to an emergency department, the important role of the family physician is stressed in a review by Sinclair and Hawton.

Self-poisoning accounts for more than 90 percent of cases of DSH. Substance abuse by patients with DSH depends on availability and perceived toxicity. Antidepressant drugs are used frequently. Use of selective serotonin reuptake inhibitors (SSRIs) has increased while use of tricyclic agents has decreased.

Tricyclics are much more dangerous, with a death rate from overdose of about 34 per 1 million prescriptions compared with a rate of two per 1 million for SSRIs. Nonprescription medications can also carry dangerous overdoses in DSH. In Great Britain, paracetamol (acetaminophen) overdose formerly accounted for one half of all cases of hepatic failure. Legislation limiting the number of tablets that can be purchased at one time is credited with reducing the number of fatal self-poisonings by 21 percent. Less common manifestations of DSH include skin cutting and mutilation of the eyes or genitalia.

Repetition is important in assessing patients with DSH. After the first episode, about 10 percent repeat self-harm within one year. One third of patients with a history of multiple episodes repeat within one year. Other factors predictive of repeating DSH include alcohol or substance misuse, previous psychiatric illness, unemployment, and low social status. The acts are highly impulsive, making availability of method crucial in repetition. Approximately 1 percent of patients with DSH die by suicide within one year of an event of self-harm. The risk of suicide is greater if the acts of DSH were planned and committed alone, a suicide note was written, attempts were made to avoid discovery, medical attention was not sought, or the patient was angry that the suicide attempt failed.

After treatment of the presenting poisoning or injury, patients must be screened for psychiatric illness. More than 70 percent are likely to be depressed, and approximately 36 percent abuse alcohol or other substances. About one half have significant comorbidities, and many have a history of being sexually abused as children. Systematic reviews have not found good evidence for pharmacologic or psychologic therapies for DSH, but low-dose neuroleptic agents are associated with a reduction in repetition. Brief psychologic interventions targeting depression and hopelessness, and encouraging problem-solving have shown promise in clinical studies.