Use of paracetamol for suicide and non-fatal poisoning in the UK and France: are restrictions on availability justified?

The hazards of gastric lavage for intentional self-poisoning in a resource poor location

OBJECTIVE

The 10-20% case fatality found with self-poisoning in the developing world differs markedly from the 0.5% found in the West. This may explain in part why the recent movement away from the use of gastric lavage in the West has not been followed in the developing world. After noting probable harm from gastric lavage in Sri Lanka, we performed an observational study to determine how lavage is routinely performed and the frequency of complications.

CASE SERIES

Fourteen consecutive gastric lavages were observed in four hospitals. Lavage was given to patients unable or unwilling to undergo forced emesis, regardless of whether they gave consent or the time elapsed since ingestion. It was also given to patients who had taken non-lethal ingestions. The airway was rarely protected in patients with reduced consciousness, large volumes of fluid were given for each cycle (200 to more than 1000 ml), and monitoring was not used. Serious complications likely to be due to the lavage were observed, including cardiac arrest and probable aspiration of fluid. Health care workers perceived lavage as being highly effective and often life-saving; there was peer and relative pressure to perform lavage in self-poisoned patients.

CONCLUSIONS

Gastric lavage as performed for highly toxic poisons in a resource-poor location is hazardous. In the absence of evidence for patient benefit from lavage, (and in agreement with some local guidelines), we believe that lavage should be considered for few patients - in those who have recently taken a potentially fatal dose of a poison, and who either give their verbal consent for the procedure or are sedated and intubated. Ideally, a randomized controlled trial should be performed to determine the balance of risks and benefits of safely performed gastric lavage in this patient population.

Pack-size legislation reduces severity of paracetamol overdoses in Ireland

BACKGROUND

Legislation was introduced in Ireland in October 2001 to control the sale of paracetamol in non-pharmacy outlets. Preparations are now limited to 12 tablets per pack and only one pack can be sold per transaction.

AIM

To assess the impact of this legislation on acute deliberate paracetamol overdoses.

METHODS

We reviewed acute deliberate paracetamol overdoses reported during two 24-months periods before and after October 2001. We grouped cases according to the number of tablets taken and compared the periods using chi-square and Mann-Whitney tests.

RESULTS

The number of tablets taken in acute deliberate paracetamol overdose fell significantly after October 2001 (chi2 = 11.663, P = 0.0029). Fewer cases involved 12-24 tablets (U = 74, P < 0.001) and fewer cases involved more than 24 tablets (U = 131.5, P = 0.0006).

CONCLUSION

Legislation controlling sale and packaging of paracetamol preparations appears to be associated with a significant fall in the number of tablets taken in acute deliberate paracetamol overdoses.

Restricting Access to Methods of Suicide

Abstract. Restriction of access to means for suicidal behavior, especially dangerous methods, is a key element in most national suicide prevention strategies. In this paper the rationale for this is discussed, including the fact that suicidal impulses are often brief, that availability of a method may influence both the occurrence and outcome of a suicidal act, and that if a favored means becomes less available it does not always result in substitution by another method. Examples of evidence for the effectiveness of restricting availability of suicidal methods on subsequent suicidal behavior are presented, plus the supporting findings from studies of long-term survivors of serious suicide attempts in which only a minority have gone on to die in subsequent suicide attempts. Finally, factors likely to determine the effectiveness of modifying access to means for suicide are considered, together with the main elements that need to be addressed in evaluation.

Restrictions in Availability of Drugs Used for Suicide

Abstract. Availability of drugs with high lethality has been hypothesized to increase the risk of self-poisoning suicides. A literature search concerning deliberate self-poisoning and the effect of restricting access to drugs was conducted, and the effect of restrictions in availability of barbiturates, tricyclic antidepressants, dextropropoxyphene, and weak analgesics was reviewed. The correlations between method-specific and overall suicide rates and sales figures for barbiturates, dextropropoxyphene, weak analgesics, and tricyclic antidepressants were reviewed. It is concluded that restriction in availability of drugs with high case fatality should be a part of suicide prevention strategies.

Paracetamol availability and recent changes in paracetamol poisoning: is the 1998 legislation limiting availability of paracetamol being followed?

OBJECTIVE

To determine the degree of adherence to legislation introduced in 1998 restricting the availability of over the counter paracetamol.

DESIGN

A prospective observational study.

SETTING

An emergency department in an inner city London teaching hospital. Pharmacy and non-pharmacy outlets in south London.

MAIN OUTCOME MEASURES

(1) The source of paracetamol ingested by 107 patients presenting with an acute paracetamol overdose (2001-2003) and (2) the ability to purchase paracetamol from pharmacy and non-pharmacy outlets in a manner contravening paracetamol pack size legislation (2004).

RESULTS

Potentially toxic amounts of paracetamol in excess of pack size restrictions were purchased in 70% (17 of 24) of outlets. Forty six per cent of patients who had ingested a potentially toxic dose of paracetamol obtained the tablets in a manner contravening the 1998 legislation.

CONCLUSION

Legislation limiting the availability of over the counter paracetamol is not being adhered to in south London. A significant number of patients ingesting a potentially toxic dose of paracetamol report purchasing the tablets in a manner contravening the legislation. Studies that attempt to assess the impact of the legislation need to be interpreted in the context of these results. Measures to enforce current legislation may help to reduce the severity of paracetamol poisoning in the UK.

Temporal changes in suicide rates for persons treated and not treated with antidepressants in Denmark during 1995-1999

OBJECTIVE

To compare the temporal changes in suicide rate among patients treated with antidepressants with the change in suicide rate among persons who have not been treated with antidepressants during 1995-1999.

METHOD

In a historic prospective national pharmacoepidemiological register linkage study by using four Danish registers we included 438,625 patients who had purchased antidepressants, and compared them with 1,199,057 population based control persons. The annual rate of suicide was estimated using Poisson regression analyses.

RESULTS

The suicide rate decreased for persons treated with antidepressants as well as for persons not treated with antidepressants. The proportion of persons, who committed suicide and who had not been treated with antidepressants decreased. The reduction in suicide rate was more pronounced among persons treated with SSRIs or older antidepressants than among persons not treated with antidepressants.

CONCLUSION

Several factors contribute to the decreasing suicide rate. The most pronounced decrease in suicide rate was found among persons treated with antidepressants.

Acute liver failure: a review

Since publication of the first descriptions of acute liver failure (ALF) as a distinct clinical entity in the 1950's, the understanding of the pathophysiologic mechanisms involved and the management options have increased substantially. ALF still represents a major challenge for todays hepatologists, because it can rapidly lead to multiorgan failure and death that may be preventable with appropriate intervention. This article summarizes the basic patho-physiology underlying ALF, compares epidemiologic trends in the United States, the United Kingdom, and the Far East, and reviews prognostic markers and treatment options for ALF.

Adolescent suicide and suicidal behavior

This review examines the descriptive epidemiology, and risk and protective factors for youth suicide and suicidal behavior. A model of youth suicidal behavior is articulated, whereby suicidal behavior ensues as a result of an interaction of socio-cultural, developmental, psychiatric, psychological, and family-environmental factors. On the basis of this review, clinical and public health approaches to the reduction in youth suicide and recommendations for further research will be discussed.

Deliberate self-poisoning with acetaminophen: a comparison with other medications

BACKGROUND

Acetaminophen is the most common drug employed in deliberate self-poisoning (DSP) in many countries and can lead to acute liver failure. The purpose of the present study was to compare DSP with acetaminophen with DSP with other medications.

METHODS

From January 2001 to December 2002, all patients admitted after DSP to Soroka University Hospital in Beer-Sheva, Israel, were identified. Demographic data and medical history were obtained retrospectively.

RESULTS

There were 282 incidences of DSP in the study period. The mean age of 94 patients with an acetaminophen overdose was lower than that of patients who had attempted DSP with other medications (24.8 vs. 34.6 years, p<0.001). There was no gender or ethnic difference between the groups. Patients with DSP with acetaminophen were less likely to make recurrent attempts (23.4% vs. 39.9% p=0.006), less likely to have psychiatric disorders (32% vs. 59% p<0.001), and had a shorter hospital stay (1.7 vs. 2.1 days, p=0.05). The acetaminophen group had less of an impairment in level of consciousness (84% vs. 52.1% p<0.001) and had less need for ICU care (6.4% vs. 14.9%, p=0.04). Serum levels were checked in 68 (72.3%) of the patients in the acetaminophen group and they were found to be high in 6 (8.8%) of them (95% CI 2.1-15.5%).

CONCLUSION

Taking an overdose of acetaminophen is a common method of DSP, with patients tending to have a more benign presentation and shorter hospital stay than those who attempt DSP with other medications. Further research on the optimal care of these patients and multi-disciplinary approaches to DSP prevention are needed.

Acetaminophen-induced acute liver failure: results of a United States multicenter, prospective study

Severe acetaminophen hepatotoxicity frequently leads to acute liver failure (ALF). We determined the incidence, risk factors, and outcomes of acetaminophen-induced ALF at 22 tertiary care centers in the United States. Detailed prospective data were gathered on 662 consecutive patients over a 6-year period fulfilling standard criteria for ALF (coagulopathy and encephalopathy), from which 275 (42%) were determined to result from acetaminophen liver injury. The annual percentage of acetaminophen-related ALF rose during the study from 28% in 1998 to 51% in 2003. Median dose ingested was 24 g (equivalent to 48 extra-strength tablets). Unintentional overdoses accounted for 131 (48%) cases, intentional (suicide attempts) 122 (44%), and 22 (8%) were of unknown intent. In the unintentional group, 38% took two or more acetaminophen preparations simultaneously, and 63% used narcotic-containing compounds. Eighty-one percent of unintentional patients reported taking acetaminophen and/or other analgesics for acute or chronic pain syndromes. Overall, 178 subjects (65%) survived, 74 (27%) died without transplantation, and 23 subjects (8%) underwent liver transplantation; 71% were alive at 3 weeks. Transplant-free survival rate and rate of liver transplantation were similar between intentional and unintentional groups. In conclusion, acetaminophen hepatotoxicity far exceeds other causes of acute liver failure in the United States. Susceptible patients have concomitant depression, chronic pain, alcohol or narcotic use, and/or take several preparations simultaneously. Education of patients, physicians, and pharmacies to limit high-risk use settings is recommended.

Age and paracetamol self-poisoning

BACKGROUND

Whereas paracetamol poisoning is predominantly seen in adolescents and young adults, the majority of paracetamol associated deaths occur in an older population.

AIMS

The aim of the present study was to evaluate age as a risk factor for fulminant hepatic failure (FHF) and death in a large population of patients with paracetamol poisoning.

PATIENTS

A total of 746 patients transferred to a specialised unit with severe paracetamol poisoning and 273 unselected patients admitted from the local region over a 10 year period.

METHODS

A partly retrospective study based on hospital charts. The risk associated with age was evaluated by multivariate analysis.

RESULTS

Paracetamol poisoning most frequently occurred in the age group 15-24 years. Transferred patients were significantly older than local patients (median age 37 years v 29 years; p = 0.0006). In contrast, FHF and death from paracetamol poisoning most frequently occurred in patients aged 40 years or above. In a logistic regression analysis, "age >/=40 years" was associated with an excess risk of FHF (odds ratio (OR) 2.33 (95% confidence interval (CI) 1.50-3.64)) and death or liver transplantation (OR 4.18 (95% CI 2.17-8.05)). In addition, older age was associated with other risk factors for paracetamol hepatotoxicity such as regular alcohol abuse and late presentation.

CONCLUSIONS

Age 40 years or above was identified as a significant independent risk factor for FHF and mortality following paracetamol overdose. Patients aged 40 years or above should be considered as high risk patients, in particular when older age appears in combination with regular alcohol abuse or late presentation.

UK legislation on analgesic packs: before and after study of long term effect on poisonings

OBJECTIVE

To evaluate the long term effect of legislation limiting the size of packs of analgesics sold over the counter.

DESIGN

Before and after study.

SETTING

Suicides in England and Wales, data from six liver units in England and Scotland and five general hospitals in England, and UK data on sales of analgesics, between September 1993 and September 2002.

DATA SOURCES

Office for National Statistics; six liver units in England and Scotland; monitoring systems in general hospitals in Oxford, Manchester, and Derby; and Intercontinental Medical Statistics Health UK.

MAIN OUTCOME MEASURES

Deaths by suicidal overdose with paracetamol, salicylates, or ibuprofen; numbers of patients admitted to liver units, listed for liver transplant, and undergoing transplantations for paracetamol induced hepatotoxicity; non-fatal self poisonings with analgesics and numbers of tablets taken; and sales figures for analgesics.

RESULTS

Suicidal deaths from paracetamol and salicylates were reduced by 22% (95% confidence interval 11% to 32%) in the year after the change in legislation on 16 September 1998, and this reduction persisted in the next two years. Liver unit admissions and liver transplants for paracetamol induced hepatotoxicity were reduced by around 30% in the four years after the legislation. Numbers of paracetamol and salicylate tablets in non-fatal overdoses were reduced in the three years after the legislation. Large overdoses were reduced by 20% (9% to 29%) for paracetamol and by 39% (14% to 57%) for salicylates in the second and third years after the legislation. Ibuprofen overdoses increased after the legislation, but with little or no effect on deaths.

CONCLUSION

Legislation restricting pack sizes of analgesics in the United Kingdom has been beneficial. A further reduction in pack sizes could prevent more deaths.

Single dose oral paracetamol (acetaminophen) for postoperative pain

BACKGROUND

Paracetamol (acetaminophen) and non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for the relief of mild and moderate pain arising from headache, musculoskeletal conditions and dysmenorrhoea. A prior Cochrane systematic review concluded that paracetamol is also effective for postoperative pain, but additional trials have since been published. This review sought to evaluate the efficacy and safety of paracetamol using current data, and to compare the findings with other analgesics evaluated in the same way.

OBJECTIVES

To assess the efficacy of single dose oral paracetamol for the treatment of acute postoperative pain.

SEARCH STRATEGY

We searched the Cochrane Library (Issue 3, 2002), the trials register of the Cochrane Pain, Palliative and Supportive Care group (November 2002); MEDLINE (1966 to May 1996); PubMed (1996 to August 2001); EMBASE (1980 to 1996); the Oxford Pain Relief Database (1950 to 1994); and reference lists of articles in order to update an existing version of the review.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of paracetamol for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. The area under the 'pain relief versus time' curve was used to derive the proportion of patients with paracetamol or placebo experiencing least 50% pain relief over four to six hours using validated equations. The number-needed-to-treat (NNT) was calculated using 95% confidence intervals. Information on adverse effects was also collected.

MAIN RESULTS

Forty-seven reports that enrolled 4186 patients (2561 patients were treated with a single oral dose of paracetamol and 1625 with placebo) met the inclusion criteria and were included in the analyses. The NNTs for at least 50% pain relief over four to six hours following a single dose of paracetamol were as follows: 325 mg NNT 3.8 (2.2 to 13.3); 500 mg NNT 3.5 (2.7 to 4.8); 600/650 mg NNT 4.6 (3.9 to 5.5); 975/1000 mg NNT 3.8 (3.4 to 4.4); and 1500 mg NNT 3.7 (2.3 to 9.5). Sub-group analysis showed no significant differences between smaller and larger trials, or lower and higher quality trials. Drug-related study withdrawals were rarely reported. Studies reported a variable incidence of adverse effects that were generally mild and transient. There were no statistically significant differences in the frequency of reported adverse effects between paracetamol 975/1000 mg and placebo.

REVIEWER'S CONCLUSIONS

Single doses of paracetamol are effective analgesics for acute postoperative pain and give rise to few adverse effects.

The epidemiology of self-poisoning in the UK

Self-poisoning by ingestion or inhalation is common, and it is important to study its various epidemiological manifestations with clear definitions. Data on fatal self-poisonings are recorded nationally within the UK and are codified according to the International Classification of Diseases (ICD) revision relevant at the time. Most fatal self-poisonings are codified as suicides, accidental deaths or undetermined deaths ('open verdicts'). Non-fatal self-poisoning data, whether accidental or as a manifestation of deliberate self-harm, are recorded through hospital discharge information nationally but are not routinely published in the same way as mortality data. The bulk of the UK's published epidemiological information on nonfatal self-poisoning episodes is largely based on individual hospitals' admission or discharge records ('special studies'). After establishing definitions for different self-poisoning categories we discuss the published data on self-poisoning as they relate to suicide, accidental self-poisoning and deliberate self-harm in the UK.

Paracetamol poisoning--impact of pack size restrictions

BACKGROUND

Pack sizes of paracetamol available to the public were reduced by legislation in 1998.

OBJECTIVE

To study the effect of the legislation on paracetamol poisoning related admissions to an accident and emergency department and to a tertiary referral liver unit.

METHOD

Data were obtained from the University Hospitals, Birmingham, UK (UHB) Trust Information Service and the Queen Elizabeth Hospital liver unit records on (a) the number of patients admitted to hospital because of paracetamol overdose and (b) the number of patients admitted to the liver unit with parcetamol-induced hepatotoxicity.

RESULTS

Prior to legislation, an average of 360 people a year were admitted to UHB. However, following the change in legislation the number of admissions has fallen to an average of 250 people per year. This represents a reduction of 31%. Prior to legislation, an average of 76 people per year were admitted to the liver unit. Post-legislation this number has dropped to an average of 38 per year representing a reduction of 50%.

CONCLUSION

Legislation restricting paracetamol pack-size reduced the incidence and severity of poisoning.

United Kingdom legislation on pack sizes of analgesics: background, rationale, and effects on suicide and deliberate self-harm

Following increasing concern in the UK about the mortality and morbidity associated with self-poisoning with analgesics, especially paracetamol (Tylenol, acetaminophen), legislation was introduced in 1998 to modify packs sold over-the-counter. The most important change was a reduction in the maximum size of packs. In this paper the background to the legislation, the rationale behind it, and its early impact are reviewed. The changes have had significant positive initial benefits on the mortality and morbidity associated with self-poisoning with analgesics.

The effect of recalling paracetamol on hospital admissions for poisoning in Western Australia

OBJECTIVES

To assess the effect of two recalls of paracetamol products on rates of intentional and unintentional overdoses of paracetamol in all age groups, as well as any effect on poisoning by other agents.

DESIGN

A before-and-after epidemiological study using data from the Western Australian Health Services Research Linked Database, which records all admissions to public and private hospitals throughout the State.

MAIN OUTCOME MEASURES

Hospital admissions in Western Australia for poisonings with all agents, including paracetamol and other over-the-counter analgesics.

RESULTS

There were 11 752 admissions for poisoning from 1996 to 2001. Paracetamol was the primary poisoning agent in 2266 (19.3%) admissions, aspirin in 120 (1%) and ibuprofen in 277 (2%). There was a significant decrease in the admission rate for paracetamol poisoning when sales were restricted in 2000 (rate ratio, 0.82; 95% CI, 0.68-0.99) compared with the same period in other years. There was no increase in poisoning with other agents at this time. However, admissions for paracetamol overdose also showed a large random variation that tended to obscure any effect.

CONCLUSIONS

Our study highlights the need to control for random as well as seasonal fluctuations in admission rates, and for restrictions on paracetamol sales to last for several months across all retail outlets. Limiting access to paracetamol may reduce paracetamol poisonings without a coincident increase in the use of other agents

The Esperance primary prevention of suicide project

BACKGROUND

Suicide has been a major community concern in Esperance, a geographically isolated port on the south coast of Western Australia.

AIMS

To evaluate the effect of three evidence-based initiatives for the primary prevention of suicide: (i) providing suicide awareness sessions for staff members in health, education and social services; (ii) limiting the sale of over the counter analgesics (aspirin and paracetamol) to packets containing less than the minimum lethal dose; and (iii) implementing Commonwealth media guidelines in the reporting of suicides by media.

METHODS

Changes in knowledge, awareness, attitudes, comfort and use, before and after each intervention were assessed using standardized instruments and pro forma derived from previous work, such as the Youth Suicide Prevention Training Manual and Suicide Intervention Beliefs Scale. Percentage changes in the number of retail outlets selling over the counter analgesics to less than potentially lethal quantities (less than 8 g of paracetamol or aspirin) were also measured. Media representatives were interviewed to gain their perceptions of Commonwealth Guidelines for the reporting of suicide, and encouraged to consult the project team before reporting suicide related issues.

RESULTS

The baseline survey illustrated that mental health staff and general practitioners were more aware of suicide issues, risk factors for suicide and awareness of professional and ethical responses than staff from other services, and were more willing to raise the issue with a person at risk. Thirty-three subjects participated in suicide awareness training of whom 21 (66%) returned questionnaires. There were significant increases in awareness of suicide-related issues and risk factors, as well as reported levels of knowledge of professional and ethical responses and comfort, competence and confidence levels when assisting a person at risk. Only three media representatives were aware of the Commonwealth Health Department Guidelines for reporting suicide and only one believed that the guidelines influenced their reporting. The local newspapers subsequently contacted the researchers to check that their reporting met the guidelines. As regards access to analgesics, one out of seven retailers agreed to implement the strategy (pending agreement from other retailers), another claimed increased awareness of the danger of analgesics, and three maintained that they would attempt to monitor excessive amounts sold to one individual.

CONCLUSIONS

Local initiatives can improve the awareness and knowledge of staff in the assessment of suicide risk, as well as of local media. These need to be complemented by initiatives at State or Commonwealth level to produce change in statewide media, or sales of over the counter analgesics.

Paracetamol overdose: an evidence based flowchart to guide management

A flowchart for the management of patients with paracetamol poisoning is presented to help clinicians in the emergency department.

Alcohol exposure and paracetamol-induced hepatotoxicity

Most instances of hepatotoxicity due to paracetamol in the United Kingdom and Australia are the result of large overdoses of the drug taken with suicidal or parasuicidal intent. In contrast, serious hepatotoxicity at recommended or near-recommended doses for therapeutic purposes has been reported, mainly from the United States and in association with chronic alcohol use, leading to the widely held belief that chronic alcoholics are predisposed to paracetamol-related toxicity at relatively low doses. Yet the effects of alcohol on paracetamol metabolism are complex. Studies performed in both experimental animals and humans indicate that chronic alcohol use leads to a short-term, two- to threefold increase in hepatic content of cytochrome P4502E1, the major isoform responsible for the generation of the toxic metabolite from paracetamol, although increased oxidative metabolism of paracetamol at recommended doses has not been demonstrated clinically. A reduced hepatic content of glutathione, required to detoxify the reactive metabolite, has been documented in chronic alcoholics, due probably to associated fasting and malnutrition, providing a metabolic basis for any possible predisposition of this group to hepatotoxicity at relatively low paracetamol doses. Simultaneous alcohol and paracetamol ingestion reduces oxidative metabolism of paracetamol in both rodents and humans, predominantly as a consequence of depletion in cytosol of free NADPH. The possibilities that chronic alcohol use may predispose to paracetamol-related hepatotoxicity and that alcohol taken with paracetamol may protect against it, based on these metabolic observations, are examined in this review.

Paracetamol recall: a natural experiment influencing analgesic poisoning

OBJECTIVES

To determine whether the occurrence of paracetamol and non-paracetamol analgesic deliberate self-poisoning (DSP) and accidental paediatric poisoning was affected by two periods of recall of paracetamol products.

DESIGN

Retrospective, observational audit of proportions of poisonings with tablet and capsule formulations of paracetamol, ibuprofen and aspirin products during two recall periods compared with the number of poisonings during the same periods of the previous three years.

SETTING

A national poisons information centre and a regional toxicology service.

MAIN OUTCOME MEASURES

Rates of DSP and accidental paediatric poisoning with paracetamol, ibuprofen and aspirin.

RESULTS

During the two recall periods, there was a significant increase in ibuprofen DSP calls to the poisons information centre (RR, 1.86; 95% Cl, 1.41-2.44; P = 0.001). There was no significant change in paracetamol or aspirin DSP calls over the two recall periods. However, there was a non-significant reduction in DSP calls with paracetamol in the first recall period alone (P = 0.057). There was a significant increase in the proportion of aspirin DSP presentations for the toxicology service (RR, 3.33; 95% CI, 0.97-11.4; P = 0.043), but no significant changes in paracetamol and ibuprofen DSP presentations. For accidental paediatric ingestions there was a significant increase in the proportion of ibuprofen calls (RR, 2.35; 95% CI, 1.85-2.98; P = 0.001), but no significant change in paracetamol or aspirin calls.

CONCLUSIONS

Reduced paracetamol availability increased poisoning with alternative analgesics, but had little effect on the incidence of paracetamol poisoning. Restriction of paracetamol-containing products may inadvertently increase poisoning with potentially more toxic agents.

A NO-releasing derivative of acetaminophen spares the liver by acting at several checkpoints in the Fas pathway

NCX-701 is a nitric oxide (NO)-releasing acetaminophen (APAP) derivative. In the present study we demonstrated that NCX-701 is as effective as APAP in controlling body temperature in a rat model of endotoxin-induced fever. Liver toxicity is a major complication of APAP overdosing. To investigate whether NCX-701 is hepatotoxic, BALB/C mice were injected with 100 - 500 mg kg(-1) APAP or NCX-701 alone or in combination (i.e. 500 mg kg(-1) of both compounds). Our results demonstrated that although APAP caused a dose-dependent liver injury, NCX-701 was completely devoid of liver toxicity. At the dose of 500 mg kg(-1) APAP caused an approximately 40 fold increase of AST plasma levels and extensive centrilobular necrosis. APAP and NCX-701 share the same metabolic pathway as demonstrated by the time-course of APAP-glucuronide concentrations in plasma and liver. NCX-701 was safe in mice with pre-existing chronic liver disease. Indeed, while C57BL6 transgenic mice expressing the hepatitis B virus (HBV) at the age of 8 months were significantly more susceptible to liver damage induced by APAP (500 mg kg(-1)) than their congenic littermates, treating HBV-transgenic mice with NCX-701, 500 mg kg(-1), caused no damage. Co-administration of NCX-701 at the dose 500 mg kg(-1) to mice treated with APAP, 500 mg kg(-1), completely protected against liver damage induced by APAP. APAP, but not NCX-701, upregulated liver Fas and Fas Ligand mRNA expression in vivo. Incubating mouse hepatocytes with APAP, but not with NCX-701, increased cell surface Fas expression and sensitized hepatocytes to death induced by challenge with a Fas-agonistic antibody. Collectively, these observations suggest that APAP toxicity is Fas mediated and that NCX-701 spares the liver by acting at several checkpoints in the Fas pathway.

Effects of legislation restricting pack sizes of paracetamol and salicylate on self poisoning in the United Kingdom: before and after study

OBJECTIVE

To evaluate the effects on suicidal behaviour of legislation limiting the size of packs of paracetamol and salicylates sold over the counter.

DESIGN

Before and after study.

SETTING

UK population, with detailed monitoring of data from five liver units and seven general hospitals, between September 1996 and September 1999.

SUBJECTS

People who died by suicidal or accidental overdose with paracetamol or salicylates or who died of undetermined causes; patients admitted to liver units with hepatic paracetamol poisoning; patients presenting to general hospitals with self poisoning after taking paracetamol or salicylates.

MAIN OUTCOME MEASURES

Mortality from paracetamol or salicylate overdose; numbers of patients referred to liver units or listed for liver transplant; numbers of transplantations; numbers of overdoses and tablets taken; blood concentrations of the drugs; prothrombin times; sales to pharmacies and other outlets of paracetamol and salicylates.

RESULTS

Numbers of tablets per pack of paracetamol and salicylates decreased markedly in the year after the change in legislation on 16 September 1998. The annual number of deaths from paracetamol poisoning decreased by 21% (95% confidence interval 5% to 34%) and the number from salicylates decreased by 48% (11% to 70%). Liver transplant rates after paracetamol poisoning decreased by 66% (55% to 74%). The rate of non-fatal self poisoning with paracetamol in any form decreased by 11% (5% to 16%), mainly because of a 15% (8% to 21%) reduction in overdoses of paracetamol in non-compound form. The average number of tablets taken in paracetamol overdoses decreased by 7% (0% to 12%), and the proportion involving >32 tablets decreased by 17% (4% to 28%). The average number of tablets taken in salicylate overdoses did not decrease, but 34% fewer (2% to 56%) salicylate overdoses involved >32 tablets. After the legislation mean blood concentrations of salicylates after overdose decreased, as did prothrombin times; mean blood concentrations of paracetamol did not change.

CONCLUSION

Legislation restricting pack sizes of paracetamol and salicylates in the United Kingdom has had substantial beneficial effects on mortality and morbidity associated with self poisoning using these drugs.

Protective effect of stiripentol on acetaminophen-induced hepatotoxicity in rat

Acetaminophen (APAP) is mainly eliminated at a therapeutic dose through glucuronidation and sulfatation and a small fraction is oxidized by cytochromes P450 (CYP) 2E1, 3A4, and 1A2 to N-acetyl-p-benzoquinone-imine (NAPQI), a highly reactive metabolite further conjugated with glutathione into APAP-GSH, and then metabolized to APAP-cystein and APAP-mercapturate excreted in urine. After APAP overdose, the glucuronidation and sulfatation pathways are saturated and the production of NAPQI increases, causing hepatic injury. Stiripentol (STP); (200 mg/kg), an anticonvulsant drug inhibitor of CYP1A2 and CYP3A4 in vivo in humans was tested against APAP-induced toxicity in rat in comparison with N-acetylcysteine (NAC; 100 mg/kg). The mortality rates 24 h after APAP overdose (2 x 500 mg/kg) were 63% (control), 38% (NAC), 0% (STP), and 4% (STP + NAC). The mean plasma transaminase concentrations 5 and 24 h after overdose were significantly higher in control than in STP and NAC groups. The percentage of rats without microscopic liver necrosis 5 h after APAP overdose was significantly higher in rats receiving STP (100%), NAC (83%), or STP + NAC (83%) than controls (42%). In another experiment, four similar groups were administered 50 mg/kg APAP. Plasma AUC(0-5 h) for APAP-GSH, APAP-cystein, and APAP-mercapturate as well as urine APAP-mercapturate mean amounts were significantly lower in STP animals than in the other groups. STP (200 mg/kg) inhibited NAPQI synthesis through CYP inhibition, thus preventing both liver necrosis and mortality in rats.

Deliberate self-poisoning presenting at a rural hospital in Northern Ireland 1976-1996: relationship to prescribing

PURPOSE

This study reports on a project to monitor deliberate self-poisoning in a rural area of Northern Ireland over a 20-year period. Comparison is made with reports from large urban centres. In addition, a local prescribing database allows assessment of any association between psychotropic drug prescription and use for deliberate self-poisoning.

MATERIALS AND METHODS

Frequency of self-poisoning, demographic details and drugs used were recorded for all episodes of deliberate self-poisoning occurring at Craigavon Area Hospital for the years 1976, 1986, 1991 and 1996. It was possible to compare prescriptions of psychotropic drugs with their use for deliberate self-poisoning between the years 1991 and 1996 in the region served by the hospital, using the Defined Daily Dose (DDD) system.

RESULTS

In this rural area the pattern of deliberate self-poisoning has changed, as in urban centres, with a rise in frequency and the male/female ratio approaching unity. The pattern of drug use has altered, with paracetamol overtaking benzodiazepines as the most commonly used agent. More recently, antidepressants have become the second most frequently used drug class for this purpose. Psychotropic medications used for self-poisoning altered in proportion to their prescription between the years 1991 and 1996.

CONCLUSIONS

In the face of a continuing rise in deliberate self-poisoning, which is effecting both urban and rural areas, care should be taken to prescribe the least toxic agent available as this is associated with likely frequency of self-poisoning for most classes of psychotropic drug.

Improvements in the packaging of drugs and chemicals may reduce the likelihood of severe intentional poisonings in adults

Because of the inconvenience and longer time required to punch out the tablets, strip packaging may reduce the number of tablets that can be readily swallowed by adults with self-poisonings. In fact, hospital-based studies of paracetamol poisoning in the U.K. and Hong Kong have shown that blister packs were associated with fewer tablets being ingested and large overdoses were mostly from loose preparations. In Australia, following the change in packaging for carbamazepine from bottles of tablets to blister packs, a marked decrease in the reported number of tablets ingested by patients was seen. Reducing the maximum number of tablets that can be available in individual preparations or prescriptions may also reduce the likelihood of severe poisonings. In France, but not in the UK, the content of each pack of paracetamol has been legally limited to 8 g. This was thought to be one reason why severe liver damage and deaths after paracetamol poisonings are less common in France than in the UK. Medicated oils containing methyl salicylate pose the threat of rapid-onset, severe salicylate poisoning if swallowed. To reduce the amount of methyl salicylate that can be readily swallowed, the methyl salicylate content and the size of the bottle and its opening should be restricted. In adults with Dettol poisoning, serious complications such as pulmonary aspiration are more likely if a large amount is ingested. Similarly, the risk may be reduced by restricting the size of bottle and its opening.

Methods of youth suicide in New Zealand: trends and implications for prevention

OBJECTIVE

One commonly suggested approach to reducing suicide is to restrict access to potentially lethal means of suicide. This paper summarises recent trends in methods of suicide among young people in New Zealand and examines the feasibility of suicide prevention through restricting access to methods of suicide.

METHOD

Data derived from official mortality statistics were used to examine trends, from 1977 to 1996, in methods of suicide among young people aged 15-24 years.

RESULTS

During the last two decades, male youth suicide rates in New Zealand doubled, from 20.3 per 100,000 in 1977 to 39.5 per 100,000 in 1996. This increase was accounted for, almost entirely, by increased use of hanging (71% of total increase) and vehicle exhaust gas (26% of total increase). Suicide rates among young females also increased, from 4 per 100,000 in 1977 to 14.3 per 100,000 in 1996. As for males, the increased female suicide rate was largely accounted for by increased rates of hanging and vehicle exhaust gas.

CONCLUSIONS

The marked increases in rates of youth suicide in New Zealand during the past two decades are accounted for, almost wholly, by increases in rates of suicide by hanging and, to a lesser extent, vehicle exhaust gas. In 1996 the majority (79.7%) of youth suicides were accounted for by these two methods: hanging (61.5%) and vehicle exhaust gas (18.2%). Both methods are widely available and difficult to restrict, implying that limiting access to means of suicide is a strategy which is unlikely to play a major role in reducing suicidal behaviour among young people in New Zealand.

Preventive interventions for youth suicide: a risk factor-based approach

OBJECTIVE

This review draws on current knowledge of risk for youth suicide to categorize strategies for intervention. Its goal is to identify areas of 'research need' and to provide an evidence base to identify 'best buy' preventive interventions for youth suicide.

METHOD

The design, development, implementation and evaluation of prevention strategies ranging from clinical interventions to population-based universal approaches are considered within five risk factor domains: individual, family, community, school and peer.

RESULTS

There is a paucity of evidence on the effects of interventions targeting depression and suicidal behaviour. Nevertheless, there are effective indicated, selective and universal interventions for important risk factors for depression and suicidal behaviour. Little evidence has emerged to support the efficacy of some traditional approaches to suicide prevention, such as school based suicide education programs and telephone hotlines.

CONCLUSIONS

Youth suicide prevention strategies in Australia have generally employed traditional approaches that focus on clinical interventions for self-harmers, restricting access to lethal means, providing services to high risk groups and enhancing general practitioner responses. Both program development and research evaluation of interventions for many important risk and protective factors for suicide have been neglected.

Attendance for self-harm in a West Midlands hospital A&E department

This article focuses on the issue of self-harm. It reviews the literature and details specifically a comparison of data collected in the accident and emergency (A&E) department of a hospital in the West Midlands in 1990 and in 1997. Both the research literature and the data collected at the hospital suggest that there is a rise in the numbers of people self-harming and presenting to A&E departments. Any changes in rates of self-harm or the demographic characteristics of the patient population are likely to have important implications for clinical services. Additionally, the links between self-harm and suicide are well documented (Hawton and Fagg, 1988; Morgan and Williams, 1994) and there is an urgent need to ensure quality service for this high-risk group. An effective assessment of the area is difficult. The limited number of comprehensive studies prohibits definitive epidemiological data. Furthermore, confusion over terminology hinders clear analysis and comparison of that which is collected.

Deliberate self-harm in adolescents in Oxford, 1985-1995

Deliberate self-harm (DSH) has been one of the major health problems of adolescents in the U.K. for many years. Any changes in rates of DSH or the demographic characteristics of the patient population are likely to have important implications for clinical services and for future suicidal behaviour. Following a decline in rates in the late 1970s and mid 1980s, there were signs in the late 1980s that rates were beginning to increase again. We have used data collected by the Oxford Monitoring System for Attempted Suicide on the basis of patients presenting to the general hospital in Oxford to review trends in DSH in under 20-year-olds between 1985 and 1995. There was a substantial increase in the numbers of teenage DSH patients during the 11-year study period, with an increase between 1985-1986 and 1994-1995 of 27.7% in males, 28.3% in females, and 28.1% overall. There were no demographic changes within the catchment area to explain a change of this size. As rates of repetition of DSH also increased in both sexes during the study period the overall number of episodes of DSH rose even more between 1985-1986 and 1994-1995 (+56.9% in males, +46.3% in females, and +49.4% overall). As in previous studies the majority of adolescents had interpersonal problems and/or difficulties with studying or employment. Self-poisoning with paracetamol and paracetamol compounds became increasingly common such that by 1995 these were used in almost two-thirds of overdoses. The recent increase in DSH in adolescents has important implications for general hospital and adolescent psychiatric services. The greater frequency of repetition of DSH may herald increased future suicide rates. The case for restricting the amount of paracetamol available is overwhelming. Evaluative trials of specific interventions following adolescent DSH are urgently required.

Effects of a drug overdose in a television drama on presentations to hospital for self poisoning: time series and questionnaire study

OBJECTIVES

To determine whether a serious paracetamol overdose in the medical television drama Casualty altered the incidence and nature of general hospital presentations for deliberate self poisoning.

DESIGN

Interrupted time series analysis of presentations for self poisoning at accident and emergency departments during three week periods before and after the broadcast. Questionnaire responses collected from self poisoning patients during the same periods.

SETTING

49 accident and emergency departments and psychiatric services in United Kingdom collected incidence data; 25 services collected questionnaire data.

SUBJECTS

4403 self poisoning patients; questionnaires completed for 1047.

MAIN OUTCOME MEASURES

Change in presentation rates for self poisoning in the three weeks after the broadcast compared with the three weeks before, use of paracetamol and other drugs for self poisoning, and the nature of overdoses in viewers of the broadcast compared with non-viewers.

RESULTS

Presentations for self poisoning increased by 17% (95% confidence interval 7% to 28%) in the week after the broadcast and by 9% (0 to 19%) in the second week. Increases in paracetamol overdoses were more marked than increases in non-paracetamol overdoses. Thirty two patients who presented in the week after the broadcast and were interviewed had seen the episode-20% said that it had influenced their decision to take an overdose, and 17% said it had influenced their choice of drug. The use of paracetamol for overdose doubled among viewers of Casualty after the episode (rise of 106%; 28% to 232%).

CONCLUSIONS

Broadcast of popular television dramas depicting self poisoning may have a short term influence in terms of increases in hospital presentation for overdose and changes in the choice of drug taken. This raises serious questions about the advisability of the media portraying suicidal behaviour.

Why has suicide increased in young males?

Several countries in the Western hemisphere have experienced a marked increase in suicide rates in young males in recent years. This article considers this phenomenon largely from the perspective of the United Kingdom, where rates of suicide in 15-24-year-old males nearly doubled in just over a decade. The possible reasons for this are considered, particularly in the context of relative stability of suicide rates in young females.

Mechanism of action and value of N-acetylcysteine in the treatment of early and late acetaminophen poisoning: a critical review

INTRODUCTION

The mechanism of action of N-acetylcysteine in early acetaminophen poisoning is well understood, but much remains to be learned of the mechanism of its possible benefit in acetaminophen poisoning presenting beyond 15 hours.

METHODS

Selective review of medical literature. N-acetylcysteine should be used in all cases of early acetaminophen poisoning where the plasma acetaminophen concentration lies "above the line;" which line is chosen depends on individual preference and whether enzyme induction is suspected. Particular care should be taken with the use of the nomogram for patients with chronic excess ingestion of acetaminophen or for those who have taken slow-release formulations.

CONCLUSIONS

While there is a trend suggesting a beneficial effect of N-acetylcysteine in some patients presenting beyond 15 hours, further research is necessary to establish just how effective N-acetylcysteine is, particularly in patients presenting with fulminant hepatic failure. Candidate mechanisms for a beneficial effect in-clude improvement of liver blood flow, glutathione replenishment, modification of cytokine production, and free radical or oxygen scavenging. Hemody-namic and oxygen delivery and utilization parameters must be monitored carefully during delayed N-acetylcysteine treatment of patients with fulminant hepatic failure, as unwanted vasodilation may be deleterious to the maintenance of mean arterial blood pressure.

Trends in deliberate self-harm in Oxford, 1985-1995. Implications for clinical services and the prevention of suicide

BACKGROUND

Deliberate self-harm (DSH) has been a major health problem in the UK for nearly three decades. Any changes in rates of DSH or the demographic characteristics of the patient population are likely to have important implications for clinical services and suicide prevention.

METHOD

Data collected by the Oxford Monitoring System for Attempted Suicide were used to review trends in DSH between 1985-1995.

RESULTS

There was a substantial increase in DSH rates during the 11-year study period, with a 62.1% increase in males and a 42.2% increase in females. The largest rise was in 15-24-year-old males (+ 194.1%). Changes in DSH rates correlated with changes in national suicide rates in both males and females in this age group. Rates of repetition of DSH increase in both genders during the study period. Paracetamol self-poisoning has continued to increase, half of all overdoses in 1995 involving paracetamol, and antidepressant overdoses have become more common.

CONCLUSIONS

The increase in DSH, especially in young males, has important implications for general hospital DSH and medical services. It may herald a reversal of recent progress towards achievement of national suicide targets.