Self-harm
Self-harm refers to any act of self-poisoning or self-injury (this does not include drinking too much alcohol, or accidental self-harm).
Self-harm is common among younger people. A survey of young people aged 15-16 years estimated that more than 10% of girls and more than 3% of boys had self-harmed in the previous year. For all age groups, annual prevalence is approximately 0.5%.
One systematic review (Owens, 2002) reported that a median of 16% of self-harm patients repeat within one year.
People who attend an emergency department after an incident of self-harm will often have visited their GP in the previous month (approximately half).
Risk assessment tools and scales
Risk assessment tools are described by NICE as 'crude'. They are NOT recommended for:
Interventions for self-harm
NICE recommend:
General management of ingestion
Activated charcoal can help if used early (within 2 hours of ingestion). It should only be used for drugs where it is expected to be effective in reducing absorption. The patient needs to be fully conscious and able to protect their own airway.
Emetics, including ipecac (ipecacuanha), should not be used in the
management of self-poisoning.
Cathartics as a specific treatment should not be used in the management of
self-poisoning.
Gastric lavage should generally not be used unless recommended by TOXBASE.
Paracetamol
Paracetamol is involved in between 30 and 40% of acute presentations with poisoning.
It is is toxic to the liver as a result of conversion to a benzoquinonimine metabolite which is normally conjugated with the amino acid glutathione. The metabolism of paracetamol via this route is inducible, and therefore more rapid in patients on inducing drugs (e.g. phenytoin, carbamazepine, barbiturates, rifampicin, St John's Wort) or who are chronic alcoholics. Alcoholics who have recently stopped drinking are at greatest risk. Supplies of glutathione in the liver depend on the patient's diet and there is suspicion that acute starvation may therefore represent an additional risk factor to the known ones of eating disorders and chronic malnutrition.
Levels should be measured for risk assessment no earlier than 4 hours and no later than 15 hours after ingestion. Intravenous acetylcysteine is the treatment of choice.
Treatment is generally divided into four phases:-
Acetylcysteine is normally administered for 20 hours. Pseudo-allergic reactions are relatively common (5-10%) and should be treated with antihistamines. A larger proportion of patients (approx 25%) suffer nausea or vomiting. True anaphylaxis has not been observed and a history of previous reactions is not a reason not to treat.
A small proportion of patients develop renal damage from paracetamol, in the absence of any major liver damage. Renal damage is a common complication of acute liver failure and an important index of its severity.
(above taken from D Bateman. Poisoning: focus on paracetamol. J R Coll Physicians Edinb 2007; 37:332-334.)
Opiates
Opioids are commonly prescribed for treating chronic pain and are often misused and abused to achieve euphoria. Opioid overdoses can result in life-threatening effects such as respiratory depression, hypoxia, coma, bradycardia, hypotension/hypertension, and CNS depression.
Naloxone is used as an antidote for opioid overdose. It is a pure opioid competitive antagonist at all receptor sites (mu, kappa, and delta). Naloxone reverses coma and respiratory depression from all opioids, including partial agonists such as buprenorphine, without adding any agonist effects (respiratory depression, sedation, analgesia, miosis).
Benzodiazepines
Flumazenil, can help reduce the need for admission to intensive care. Although widely used, flumazenil is not currently licensed for the treatment of benzodiazepine overdose in the UK.
Flumazenil should be avoided in patients who may have ingested proconvulsants, (tricyclic antidepressants), those with a history of epilepsy, and patients who are dependent upon benzodiazepines (as it can precipitate seizures in these patients).
Flumazenil reverses the effects of benzodiazepines by competitive inhibition at the benzodiazepine binding site on the GABA-A receptor. It has been effectively used to treat overdoses of non-benzodiazepine hypnotics (Z drugs).
It has no effect on other drugs such as barbiturates, ethanol, or other GABA-mimetic agents (unless they act on the benzodiazepine receptor site).
Skin lacerations
For superficial uncomplicated injuries of 5 cm or less in length, the use of tissue adhesive should be offered as a first-line treatment option. Skin closure strips could be used instead if the patient prefers.
Children
All children who self-harm should be admitted for an overnight stay at a paediatric ward.
Owens (2002) Fatal and non-fatal repetition of self- harm: systematic review. The British Journal of Psychiatry 181: 193.
Self-harm is common among younger people. A survey of young people aged 15-16 years estimated that more than 10% of girls and more than 3% of boys had self-harmed in the previous year. For all age groups, annual prevalence is approximately 0.5%.
One systematic review (Owens, 2002) reported that a median of 16% of self-harm patients repeat within one year.
People who attend an emergency department after an incident of self-harm will often have visited their GP in the previous month (approximately half).
Risk assessment tools and scales
Risk assessment tools are described by NICE as 'crude'. They are NOT recommended for:
- Predicting future suicide or repetition of self-harm
- Determining who should and should not be offered treatment or who should be discharged
Interventions for self-harm
NICE recommend:
- 3 to 12 sessions of a psychological intervention that is specifically structured for people who self-harm
- Drug treatment as a specific intervention to reduce self-harm should not be offered
General management of ingestion
Activated charcoal can help if used early (within 2 hours of ingestion). It should only be used for drugs where it is expected to be effective in reducing absorption. The patient needs to be fully conscious and able to protect their own airway.
Emetics, including ipecac (ipecacuanha), should not be used in the
management of self-poisoning.
Cathartics as a specific treatment should not be used in the management of
self-poisoning.
Gastric lavage should generally not be used unless recommended by TOXBASE.
Paracetamol
Paracetamol is involved in between 30 and 40% of acute presentations with poisoning.
It is is toxic to the liver as a result of conversion to a benzoquinonimine metabolite which is normally conjugated with the amino acid glutathione. The metabolism of paracetamol via this route is inducible, and therefore more rapid in patients on inducing drugs (e.g. phenytoin, carbamazepine, barbiturates, rifampicin, St John's Wort) or who are chronic alcoholics. Alcoholics who have recently stopped drinking are at greatest risk. Supplies of glutathione in the liver depend on the patient's diet and there is suspicion that acute starvation may therefore represent an additional risk factor to the known ones of eating disorders and chronic malnutrition.
Levels should be measured for risk assessment no earlier than 4 hours and no later than 15 hours after ingestion. Intravenous acetylcysteine is the treatment of choice.
Treatment is generally divided into four phases:-
- 1 - Before four hours have elapsed after ingestion, blood levels are not interpretable. It is unnecessary and inappropriate to administer acetylcysteine.
- 2 - Between four and eight hours after exposure there is time to obtain a plasma concentration to decide if treatment is necessary.
- 3 - After eight hours. Only after this time should 'blind' treatment with acetylcysteine be commenced, and only then if the patient has ingested more than a potentially toxic amount: >150 mg/kg in a normal patient, less in an 'at risk' patient. Treatment can be stopped if the paracetamol level is below threshold.
- 4 - Beyond 24 hours. Acetylcysteine is most effective when given early in preventing liver damage. Its effect declines from about 12 hours and management approaches therefore change for presentations 24 hours or more after ingestion. Acetylcysteine is used at this time to treat acute liver failure, and not act as a specific paracetamol antidote. In patients who present late, it is reasonable to obtain blood results and determine treatment based on these. Samples should include liver function tests (ALT or AST (alanine or aspartate aminotransferase)), prothrombin time, serum electrolytes, and a paracetamol level, which may be undetectable even in severe liver failure.
Acetylcysteine is normally administered for 20 hours. Pseudo-allergic reactions are relatively common (5-10%) and should be treated with antihistamines. A larger proportion of patients (approx 25%) suffer nausea or vomiting. True anaphylaxis has not been observed and a history of previous reactions is not a reason not to treat.
A small proportion of patients develop renal damage from paracetamol, in the absence of any major liver damage. Renal damage is a common complication of acute liver failure and an important index of its severity.
(above taken from D Bateman. Poisoning: focus on paracetamol. J R Coll Physicians Edinb 2007; 37:332-334.)
Opiates
Opioids are commonly prescribed for treating chronic pain and are often misused and abused to achieve euphoria. Opioid overdoses can result in life-threatening effects such as respiratory depression, hypoxia, coma, bradycardia, hypotension/hypertension, and CNS depression.
Naloxone is used as an antidote for opioid overdose. It is a pure opioid competitive antagonist at all receptor sites (mu, kappa, and delta). Naloxone reverses coma and respiratory depression from all opioids, including partial agonists such as buprenorphine, without adding any agonist effects (respiratory depression, sedation, analgesia, miosis).
Benzodiazepines
Flumazenil, can help reduce the need for admission to intensive care. Although widely used, flumazenil is not currently licensed for the treatment of benzodiazepine overdose in the UK.
Flumazenil should be avoided in patients who may have ingested proconvulsants, (tricyclic antidepressants), those with a history of epilepsy, and patients who are dependent upon benzodiazepines (as it can precipitate seizures in these patients).
Flumazenil reverses the effects of benzodiazepines by competitive inhibition at the benzodiazepine binding site on the GABA-A receptor. It has been effectively used to treat overdoses of non-benzodiazepine hypnotics (Z drugs).
It has no effect on other drugs such as barbiturates, ethanol, or other GABA-mimetic agents (unless they act on the benzodiazepine receptor site).
Skin lacerations
For superficial uncomplicated injuries of 5 cm or less in length, the use of tissue adhesive should be offered as a first-line treatment option. Skin closure strips could be used instead if the patient prefers.
Children
All children who self-harm should be admitted for an overnight stay at a paediatric ward.
Owens (2002) Fatal and non-fatal repetition of self- harm: systematic review. The British Journal of Psychiatry 181: 193.
