Paracetamol self-poisoning. Characteristics, prevention and harm reduction

Adolescent Acetaminophen and Ibuprofen Self-Poisoning, 2017-2022

BACKGROUND

Acetaminophen and ibuprofen are the most common agents involved in adolescent self-poisoning. With increasing suicidality observed during the COVID-19 pandemic, we sought to compare overdose trends, severity, and outcomes for both agents.

METHODS

We performed a retrospective analysis of the National Poison Data System for acetaminophen and ibuprofen single-substance exposures in teenagers 13-19 years of age from 2017-2022. Acetaminophen and ibuprofen overdoses (per 100,000 persons) were plotted by year. Medical outcomes, clinical effects, and therapies were compared to determine if there were differences in overdose severity between the 2 agents.

RESULTS

From 2017 to 2022, US poison centers recorded 50,902 single-substance acetaminophen exposures and 41,674 single-substance ibuprofen exposures in teenagers. Cases peaked in 2021 with 40.0 versus 29.1 cases (per 100,000 persons) for acetaminophen and ibuprofen, respectively. Acetaminophen self-poisoning was significantly more likely to result in death (odds ratio, 13.92; 95% confidence interval, 2.18-581.75; P < 0.001) or inpatient admission (odds ratio, 7.38; 95% confidence interval, 7.10-7.66; P < 0.001) compared with ibuprofen. Abdominal pain and vomiting were the most common clinical effects for both agents, and unsurprisingly, acetaminophen was more likely to cause transaminitis and liver dysfunction, whereas ibuprofen was more likely to cause central nervous system depression and metabolic acidosis. For the acetaminophen group, 19 teenagers underwent organ transplantation.

CONCLUSIONS

Given the increased hospitalization and treatment resources needed for acetaminophen overdoses compared with ibuprofen, it is time to implement acetaminophen packaging policy change to protect US adolescents.

Self-poisoning with paracetamol in England: short report of characteristics of individuals and their overdoses according to source of tablets

Self-poisoning with paracetamol is the most frequently used overdose method in the UK. Psychosocial assessments were conducted by mental health clinicians with 127 consecutive individuals who presented with pure paracetamol overdoses to a large general hospital over 8 months, including asking about the source of the tablets and scoring the patients' acts on the Beck Suicide Intent scale (BSI). Patients were predominantly female (86%) and young (79% aged 12-24 years). Most had used paracetamol which was available in the home (77%). Those who purchased paracetamol for the act took double the number of tablets compared with those who used paracetamol available in the home (37 v. 18), had higher suicidal intent (mean BSI: 11 v. 7) and more often required treatment with N-acetyl cysteine (71% v. 43%). These results highlight the need for safer home storage of paracetamol and consideration of reducing pack size limits on paracetamol that can be purchased.

Risk Factors for Hepatotoxicity Due to Paracetamol Overdose in Adults

Background and Objectives: Over-the-counter availability and a good safety profile make paracetamol one of the most common analgesics in developed countries but also the leading cause of liver failure due to overdose. The objectives of the study were to identify modifiable risk factors for severe hepatotoxicity following paracetamol overdose in adults. Materials and Methods: A retrospective cohort study involved the consecutive adult patients hospitalized in a toxicological center over a period of seven years due to paracetamol overdose. Complete medical datasets of laboratory and anamnestic variables were analyzed and validated by means of logistic regression model. Results: A total of 185 patients entered the study, including 25 individuals who developed severe hepatotoxicity (plasma aminotransferases levels above 1000 UI/L) and 31 individuals with mild to moderate liver injury (plasma aminotransferases levels above upper normal range, but below 1000 UI/L). In the univariable analysis, significant hepatotoxicity risk factors were male gender, alcohol abuse, an ingested paracetamol dose, and a timespan from ingestion to hospital admission. The later one was the only significant risk factor in the multivariable model (adjusted odds ratio 1.08; 95% CI: 1.03-1.12). Conclusions: A delay in hospital admission, resulting in a delayed administration of disease-specific treatment outweighs any other known risk factors of paracetamol-induced hepatotoxicity.

Clinical Characteristics, Outcomes, Disposition, and Acute Care of Children and Adolescents Treated for Acetaminophen Toxicity

OBJECTIVE

Acetaminophen is a common cause of intentional and inadvertent overdoses among children and adolescents worldwide. Little is known about characteristics and clinical outcomes of these youths. The primary goal of this naturalistic study was to describe the psychiatric characteristics, medical management, outcomes, and dispositions of children and adolescents evaluated for excessive acetaminophen exposure.

METHODS

The Rochester Epidemiology Project database was searched for all patients ages 0-18 treated for excessive acetaminophen exposure in Olmsted County, Minnesota, during a 7-year period (2004-2010). Demographic factors, overdose intentionality, medical and psychiatric treatment, mental health and addiction history, and disposition from the emergency department (ED) were documented.

RESULTS

Of 110 cases of acetaminophen overdose (89 female patients and 21 male patients), 97 (88%) were intentional and 13 (12%) were unintentional. Fifteen patients (14%) were discharged from the ED, and 69 (63%) required admission to a medical unit. Sixty-four (59%) received N-acetylcysteine. Ninety-eight (89%) were evaluated by psychiatry, and 80 (73%) were admitted for psychiatric hospitalization. Most had at least one psychiatric diagnosis, most commonly depression (55%); 22 (20%) had a prior suicide attempt. Substance use was common, notably alcohol dependence (N=16, 15%), alcohol abuse (N=18, 16%), and cannabis abuse (N=18, 16%). All survived and recovered without liver transplant.

CONCLUSIONS

Among pediatric patients with acetaminophen overdoses, psychiatric comorbidities and substance use were common. Most received both inpatient medical and psychiatric treatment. Interventions that restrict acetaminophen access are needed for this population, as are suicide risk reduction interventions for delivery in emergency settings.

Acetaminophen Toxicity: A History of Serendipity and Unintended Consequences

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Stocks of paracetamol products stored in urban New Zealand households: A cross-sectional study

BACKGROUND

Intentional self-harm is a common cause of hospital presentations in New Zealand and across the world, and self-poisoning is the most common method of self-harm. Paracetamol (acetaminophen) is frequently used in impulsive intentional overdoses, where ease of access may determine the choice of substance.

OBJECTIVE

This cross-sectional study aimed to determine how much paracetamol is present and therefore accessible in urban New Zealand households, and sources from where it has been obtained. This information is not currently available through any other means, but could inform New Zealand drug policy on access to paracetamol.

METHODS

Random cluster-sampling of households was performed in major urban areas of two cities in New Zealand, and the paracetamol-containing products, quantities, and sources were recorded. Population estimates of proportions of various types of paracetamol products were calculated.

RESULTS

A total of 174 of the 201 study households (86.6%) had at least one paracetamol product. Study households had mostly prescription products (78.2% of total mass), and a median of 24.0 g paracetamol present per household (inter-quartile range 6.0-54.0 g). Prescribed paracetamol was the main source of large stock. Based on the study findings, 53% of New Zealand households had 30 g or more paracetamol present, and 36% had 30 g or more of prescribed paracetamol, specifically.

CONCLUSIONS

This study highlights the importance of assessing whether and how much paracetamol is truly needed when prescribing and dispensing it. Convenience of appropriate access to therapeutic paracetamol needs to be balanced with preventing unnecessary accumulation of paracetamol stocks in households and inappropriate access to it. Prescribers and pharmacists need to be aware of the risks of such accumulation and assess the therapeutic needs of their patients. Public initiatives should be rolled out at regular intervals to encourage people to return unused or expired medicines to pharmacies for safe disposal.

The Bile Acid Receptor GPBAR1 Modulates CCL2/CCR2 Signaling at the Liver Sinusoidal/Macrophage Interface and Reverses Acetaminophen-Induced Liver Toxicity

Drug-induced liver injury caused by acetaminophen (acetyl-para-aminophenol [APAP]) is the main cause of acute liver failure and liver transplantation in several Western countries. Whereas direct toxicity exerted by APAP metabolites is a key determinant for early hepatocytes injury, the recruitment of cells of innate immunity exerts a mechanistic role in disease progression, determining the clinical outcomes. GPBAR1 is a G protein-coupled receptor for secondary bile acids placed at the interface between liver sinusoidal cells and innate immunity. In this report, using genetic and pharmacological approaches, we demonstrate that whereas Gpbar1 gene deletion worsens the severity of liver injury, its pharmacological activation by 6β-ethyl-3a,7b-dihydroxy-5b-cholan-24-ol rescues mice from liver injury caused by APAP. This protective effect was supported by a robust attenuation of liver recruitment of monocyte-derived macrophages and their repolarization toward an anti-inflammatory phenotype. Macrophage depletion by gadolinium chloride pretreatment abrogated disease development, whereas their reconstitution by spleen-derived macrophage transplantation restored the sensitivity to APAP in a GPBAR1-dependent manner. RNA sequencing analyses demonstrated that GPBAR1 agonism modulated the expression of multiple pathways, including the chemokine CCL2 and its receptor, CCR2. Treating wild-type mice with an anti-CCL2 mAb attenuated the severity of liver injury. We demonstrated that negative regulation of CCL2 production by GPBAR1 agonism was promoter dependent and involved FOXO1. In conclusion, we have shown that GPBAR1 is an upstream modulator of CCL2/CCR2 axis at the sinusoidal cell/macrophage interface, providing a novel target in the treatment of liver damage caused by APAP.

Epidemiological differences of common liver conditions between Asia and the West

Liver diseases form a heterogenous group of acute and chronic disorders of varying etiologies. Not only do they result in significant morbidity and mortality, but they also lead to a marked reduction in quality of life, together with a high socioeconomic burden globally. A better understanding of their global distribution is necessary to curb the massive health-care and socioeconomic burden that they entail. Notable differences and similarities have been described between common liver disease conditions occurring in Asia and the West (Europe and North America), giving rise to the need for an updated collective appraisal of this subject. In this review, the epidemiological differences of common liver conditions, specifically acute liver failure, drug-induced liver injury, acute-on-chronic liver failure, hepatocellular carcinoma, and non-alcoholic fatty liver disease, between Asia and the West are discussed.

Characteristics and Outcomes of Acetaminophen Overdose and Hepatotoxicity in Thailand

Background and Aims: Acetaminophen (APAP) is the leading cause of drug overdose and hepatotoxicity worldwide, including in Thailand. Patterns of overdose and hospital management are known to have significant impacts on the outcomes of APAP overdose, and these factors vary from country to country. Therefore, this study aimed to analyze clinical characteristics of Thai patients with APAP overdose in terms of overdose patterns, clinical presentation, treatment and outcomes. Methods: In this retrospective analytical study, medical records of adult patients hospitalized with a diagnosis of APAP overdose at Rajavithi Hospital, Bangkok, between January 2013 and December 2017 were reviewed. Results: A total of 184 patients diagnosed with APAP overdose were included. The median age was 22 (15-76) years and the majority were female (79.9%). Most overdoses were intended self-poisoning ingestion (90.8%) with a median dose of 10.5 g (4.5-50). A total of 121 patients were treated with N-acetylcysteine with a median visit-to-N-acetylcysteine time of 2 (0.5-15) h. Overall, 15.6% developed mild hepatotoxicity (aspartate aminotransferase or alanine aminotransferase >3 times the upper limit of normal), 6.4% developed severe hepatotoxicity (aspartate aminotransferase or alanine aminotransferase >10 times the upper limit of normal and international normalized ratio >2.0) and 3 patients developed acute liver failure (1 patient resolved spontaneously and 2 patients, neither of whom had a liver transplant, died). Significant predictors for hepatotoxicity included older age, chronic alcohol drinking, repeated taking of medication for more than 8 h (staggered ingestion), long duration between ingestion and hospital visit, alcohol coingestion, abdominal pain symptoms, and acute kidney injury. Conclusions: Most cases of APAP overdose in Thailand appear to be young women with intentional ingestion. With prompt management, most patients (76.4%) did not develop significant hepatotoxicity; nevertheless, despite N-acetylcysteine therapy, hepatotoxicity including acute liver failure was observed in a small proportion of patients, particularly those with unintentional overdose and chronic alcohol drinking.

Trends in self-poisoning and psychotropic drug use in people aged 5-19 years: a population-based retrospective cohort study in Australia

OBJECTIVES

To characterise trends in self-poisoning and psychotropic medicine use in young Australians.

DESIGN

Population-based retrospective cohort study.

SETTING

Calls taken by the New South Wales and Victorian Poisons Information Centres (2006-2016, accounting for 70% of Australian poisoning calls); medicine dispensings in the 10% sample of Australian Pharmaceutical Benefits Scheme data (July 2012 to June 2016).

PARTICIPANTS

People aged 5-19 years.

MAIN OUTCOME MEASURES

Yearly trends in intentional poisoning exposure calls, substances taken in intentional poisonings, a prevalence of psychotropic use (dispensing of antidepressants, antipsychotics, benzodiazepines and medicines for attention deficit hyperactivity disorder (ADHD)).

RESULTS

There were 33 501 intentional poisonings in people aged 5-19 years, with an increase of 8.39% per year (95% CI 6.08% to 10.74%, p<0.0001), with a 98% increase overall, 2006-2016. This effect was driven by increased poisonings in those born after 1997, suggesting a birth cohort effect. Females outnumbered males 3:1. Substances most commonly taken in self-poisonings were paracetamol, ibuprofen, fluoxetine, ethanol, quetiapine, paracetamol/opioid combinations, sertraline and escitalopram. Psychotropic dispensing also increased, with selective serotonin reuptake inhibitors (SSRIs) increasing 40% and 35% July 2012 to June 2016 in those aged 5-14 and 15-19, respectively. Fluoxetine was the most dispensed SSRI. Antipsychotics increased by 13% and 10%, while ADHD medication dispensing increased by 16% and 10%, in those aged 5-14 and 15-19, respectively. Conversely, dispensing of benzodiazepines to these age groups decreased by 4% and 5%, respectively.

CONCLUSIONS

Our results signal a generation that is increasingly engaging in self-harm and is increasingly prescribed psychotropic medications. These findings indicate growing mental distress in this cohort. Since people who self-harm are at increased risk of suicide later in life, these results may foretell future increases in suicide rates in Australia.

Paracetamoloverdose Presenting to an Accident & Emergency Department of a Regional Hospital in Hong Kong

We carried out a review of the patient resuscitation records and hospital notes of paracetamol overdose patients initially treated in the Accident and Emergency Department of Tuen Mun Hospital during the period starting from January 1998 to April 1999. Altogether there were 42 patients but 46 cases were recruited in the study because 4 patients had overdose twice. Ten (22%) were male, 36 (78%) were female and young female constituted the majority of the patients Forty-three cases (93%) took an overdose of paracetamol as a means of committing suicide and 20 cases (43%) ingested 10 grams or more of paracetamol. The most common provoking causes were adjustment disorder (18 cases, 39.1%) and acute stress reaction (8 cases 17.4%). The majority of the cases presented early and within 8 hours after the overdose. Two cases had impaired liver function, 3 had prolonged prothrombin time and 5 had transient metabolic acidaemia in the absence of liver failure. All patients recovered uneventfully. Forty one cases (89%) were given N-acetylcysteine (NAC) infusion, of these 6 had toxic paracetamol level, 24 had non-toxic level because NAC was given before the availability of paracetamol level in many cases and it was undetermined for the other 11 cases. Hypersensitivity reaction to NAC infusion was common (8 cases, 21%) but there was no long term sequelae. Highly variable approach in the use of NAC was noted, we suggest to set a clinical check-list for the management of paracetamol overdose especially concerning the time to check the serum level and the initiation of NAC.

Acetaminophen (APAP) hepatotoxicity-Isn't it time for APAP to go away?

Acetaminophen (APAP) is the most commonly used drug for the treatment of pain and fever around the world. At the same time, APAP can cause dose-related hepatocellular necrosis, responsible for nearly 500 deaths annually in the United States (US) alone, as well as 100,000 calls to US Poison Control Centers, 50,000 emergency room visits and 10,000 hospitalisations per year. As an over-the-counter and prescription product (with opioids), APAP toxicity dwarfs all other prescription drugs as a cause of acute liver failure in the US and Europe, but it is not regulated in any significant way. In this review the ongoing controversy surrounding the proper role for this ubiquitous pain reliever: its history, pathogenesis, clinical challenges in recognition and management, and current regulatory status are highlighted. A new solution to a 50-year-old problem is proposed.

Psychosocial and behavioral factors in acetaminophen-related acute liver failure and liver injury

OBJECTIVES

Acetaminophen overdoses result in nearly 500 deaths annually and a much larger number of hospitalizations. Suicidal overdoses are exceeded in number in the United States by unintentional overdoses. We evaluated clinical, demographic and psychosocial factors among unintentional and intentional overdose patients whose acetaminophen (APAP) toxicity had resulted in acute liver failure. We hypothesized that APAP overdose patients would be more likely to suffer from behavioral health issues and display higher impulsivity scores than the general population.

METHODS

Within 4days of admission and initial recovery of alertness, we administered a detailed questionnaire that included questions on APAP intake (e.g., dose taken, intent, other substances ingested), the Mini International Neuropsychiatric Interview modules on depression, alcohol use, substance use, and pain disorders and The Barratt Impulsiveness Scale-11.

RESULTS

The group included 44 intentional (single time point ingestions with the intent to self-harm) and 51 unintentional (multiple time point ingestions to manage pain or other condition) APAP patients enrolled in the Acute Liver Failure Study Group registry between 2007 and 2013. Both groups were characterized by similar frequencies of chronic pain, depressive symptoms at time of ingestion and alcohol and substance use disorders, all at higher rates than the general population. Overall, APAP patients scored higher than the general population for Non-planning aspects of impulsivity, with no apparent differences between other impulsivity scores or between intentional and unintentional APAP patients.

CONCLUSIONS

Depression, mismanagement of problematic chronic pain, frequent substance abuse, and increased impulsivity appear to provide the substrate for many APAP overdoses.

Validity of the days supply field in pharmacy administrative claims data for the identification of blister packaging of medications

PURPOSE

Pharmacy claims data is often used in pharmacoepidemiology studies, but no studies to date have examined whether it was possible to identify the use of blister packs in these databases. We aimed to determine whether medications dispensed in days divisible by 7 are more likely to be blister packed than medications dispensed in other quantities.

METHODS

Community pharmacies in Manitoba were invited to participate in a mail-out survey to identify the use of blister packaging for up to 25 patients who had a solid oral medication dispensed from April 1, 2012 to March 31, 2014. Eligible medications were identified using the population-based province-wide retail pharmacy network. Algorithms for identifying the use of blister packaging were determined by comparing the proportion of fills that confirmed blister pack use between different days supply quantities.

RESULTS

Twenty-seven out of 32 pharmacies that agreed to participate completed the survey. The total number of prescriptions in the analysis was 2045 of which 131 (6.4%) were dispensed in blister packaging. Overall, prescriptions dispensed in days divisible by 7 yielded a 72.5% sensitivity, 86.6% specificity, 30.3% PPV, and 97.9% NPV compared with prescriptions dispensed in other quantities. A 28-day to 30-day comparison yielded an 87.9% sensitivity, 96.1% specificity, 64.6% PPV, and 99.0% NPV.

CONCLUSION

While the NPV was high, the PPV for identifying blister packaging using the days supply field in pharmacy claims data was modest given the low prevalence in blister pack use. The best predictor occurred when 28 days was compared with 30 days. KEY POINTS Blister packs are arranged in 4 × 7 compartments and are often used to improve adherence, but no studies have examined whether it was possible to identify the use of blister packs using the days supply field in pharmacy claims data. Findings show that a 28-day supply yielded a high sensitivity and specificity for identifying the use of blister packaging compared with a 30-day supply, but there is potential for misclassification. Future studies directed at examining subgroups that are more likely to use blister packs and replication of findings using other data sources in other jurisdictions are encouraged.

Paracetamol: overdose-induced oxidative stress toxicity, metabolism, and protective effects of various compounds in vivo and in vitro

Paracetamol (APAP) is one of the most widely used and popular over-the-counter analgesic and antipyretic drugs in the world when used at therapeutic doses. APAP overdose can cause severe liver injury, liver necrosis and kidney damage in human beings and animals. Many studies indicate that oxidative stress is involved in the various toxicities associated with APAP, and various antioxidants were evaluated to investigate their protective roles against APAP-induced liver and kidney toxicities. To date, almost no review has addressed the APAP toxicity in relation to oxidative stress. This review updates the research conducted over the past decades into the production of reactive oxygen species (ROS), reactive nitrogen species (RNS), and oxidative stress as a result of APAP treatments, and ultimately their correlation with the toxicity and metabolism of APAP. The metabolism of APAP involves various CYP450 enzymes, through which oxidative stress might occur, and such metabolic factors are reviewed within. The therapeutics of a variety of compounds against APAP-induced organ damage based on their anti-oxidative effects is also discussed, in order to further understand the role of oxidative stress in APAP-induced toxicity. This review will throw new light on the critical roles of oxidative stress in APAP-induced toxicity, as well as on the contradictions and blind spots that still exist in the understanding of APAP toxicity, the cellular effects in terms of organ injury and cell signaling pathways, and finally strategies to help remedy such against oxidative damage.

Increased availability of paracetamol in Sweden and incidence of paracetamol poisoning: using laboratory data to increase validity of a population-based registry study

PURPOSE

To estimate the incidence trend and outcome of paracetamol poisoning, in relation to increased availability of paracetamol from non-pharmacy outlets in 2009.

METHOD

Patients' serum paracetamol results over 14 years (2000-2013) from 20 (out of 21) regions in Sweden were linked to national registers of hospital care, cause of death, and prescriptions. Paracetamol poisonings were defined by serum paracetamol levels, hospital diagnoses, or cause of death. The change in incidence of poisonings following increased availability of paracetamol was analysed by using segmental regression of time series.

RESULTS

Of the 12 068 paracetamol poisonings, 85% were classified as intentional self-harm. Following increased availability from non-pharmacy outlets, there was a 40.5% increase in the incidence of paracetamol poisoning, from 11.5/100 000 in 2009 to 16.2/100 000 in 2013. Regression analyses indicated a change in the trend (p < 0.0001) but not an immediate jump in the incidence (p = 0.5991) following the increased availability. Adjusting for trends in hospital episodes for self-harm, suicides, and the sales volume of paracetamol did not influence the result. All-cause mortality at 30 days (3.2%) did not change over time.

CONCLUSIONS

The incidence of paracetamol poisoning in Sweden has increased since 2009, contrasting the decreased incidence in the period of 2007-2009. The change in trend was temporally associated with the introduction of availability of paracetamol from non-pharmacy outlets but did not appear to be related to sales volume of paracetamol or general trends in self-harm or suicides. © 2017 Commonwealth of Australia. Pharmacoepidemiology and Drug Safety © 2017 John Wiley & Sons, Ltd.

How well are national guidelines relating to the general sales of aspirin and paracetamol, adhered to by retail stores: a mystery shopper study

OBJECTIVE

To determine whether non-pharmaceutical retail outlets are aboding to the current Medicines and Healthcare products Regulatory Agency (MHRA) national guidelines for over-the-counter (OTC) sales of aspirin and paracetamol.

METHODS

Stages 1 and 2 of the study deployed eight and four medical students, respectively, to undertake a mystery shopper style investigation. Stage 1: eight medical students attempted to buy ≥ 96 tablets/capsules aspirin or paracetamol in one transaction in 62 shops. Stage 2: four medical students attempted to purchase 32 paracetamol 500 mg along with a 'flu remedy preparation also containing paracetamol, in 54 shops.

RESULTS

Stage 1 data revealed that 58% and 57% retailers sold more than the MHRA guidelines recommended for paracetamol and aspirin, respectively. We observed that 23% and 28% retailers were willing to sell ≥ 96 tablets of paracetamol or aspirin with no questions asked. Stage 2 results showed that 57% retailers sold 32 × 500 mg paracetamol in conjunction with a paracetamol-containing 'flu preparation; while 98% shops sold 16 × paracetamol 500 mg along with a paracetamol-containing 'flu remedy, with no questions asked of the shopper or advice given.

DISCUSSION

MHRA national guidelines for OTC medicines sales appear to be poorly adhered to in non-pharmacy shops. Sales of aspirin and paracetamol OTC must be better regulated in the UK to ultimately reduce morbidity and mortality rates of deliberate and accidental overdoses.

Clinical and economic characteristics of emergency department visits due to acetaminophen toxicity in the USA

OBJECTIVES

To estimate the number of acetaminophen (APAP) toxicity-related emergency department (ED) visits, and to assess their associated clinical and economic burden in the USA from 2006 to 2010.

DESIGN

Cross-sectional, retrospective, large-scale database study.

SETTING

Non-federal, non-rehabilitation, community EDs in the USA.

PARTICIPANTS

Inclusion criteria included any listed diagnosis identifying poisoning by aromatic analgesics paracetamol/APAP or associated supplementary code. Generalised linear models were used to investigate the association between outcomes of inpatient admission, mortality, requirement of invasive mechanical ventilation, charges and inpatient lengths of stay based on patient, hospital and clinical characteristics.

RESULTS

Across the 625.2 million ED visits in the USA from 2006 to 2010, 411,811 APAP-related toxicity ED visits were observed, with 45.5% resulting in inpatient admission, 4.7% requiring invasive mechanical ventilation and 0.6% involving death. Overall, the incidence proportion was 27.10 per 100,000 US population, exceeding 70 per 100,000 at age 2 years and ages 16-18 years. The total national bill was $1.06 billion per year (US$ 2014), and predominantly involved females (65.5%) and intentional self-harm (58.4%), which were notably higher within the 12-20 years age category (female(12-20 years)=74.8%, intentional self-harm(12-20 years)=71.4%). Behavioural and mental health comorbidities were relatively common and associated with an increased relative risk of admission and likelihood of charges almost entirely across all age categories of ≥12 years within the multivariable analyses. The number of ED visits did not appreciably change over time, decreasing by <2% from 2006 to 2010 (n=1351). Multivariable results also suggested no consistent change in outcomes across the study's time horizon.

CONCLUSIONS

A substantial public health impact of APAP toxicity-related cases was observed in the US from 2006 to 2010, with incidence proportions peaking at age 2 years and ages 16-18 years. After controlling for numerous factors, no consistent change was observed over the 5-year time horizon concerning outcomes of admission, mortality, invasive mechanical ventilation, charges or length of stay.

Adverse Drug Reactions in Pediatric Emergency Medicine

BACKGROUND

The pediatric population displays its own pharmacological characteristics, making children vulnerable to adverse drug reactions (ADRs).

OBJECTIVE

To determine the incidence of ADRs among the pediatric emergency department (PED) population.

METHODS

This is a descriptive, noncontrolled, prospective, and single-center study, during 4 consecutive months in the PED of Nantes University Hospital.

RESULTS

Setting up active gathering of data on ADRs enabled 121 reports of 11 095 consultations at the emergency department, which corresponds to an ADR incidence of 1.09%. Digestive and cutaneous reactions made up the majority of reactions judged as being nonserious (53%) and were mainly found in children between 2 -11 years old. Of the serious ADRs, 25% were found in the 12-15-year-old age range because of the drug overdose. The main medications administered, which were responsible for the majority of the ADRs, were an equimolar mix of oxygen and nitrogen monoxide, amoxicillin, and acetaminophen. Three means of collecting data were possible: collecting files data, oral communication, or filling a form, the last being the most used method.

CONCLUSIONS

This active data gathering shows the incidence and nature of the adverse effects as well as the age distribution in the PED population. It highlights the considerable misuse of medications among young teenagers and the high incidence of overmedication in the younger age group. This work also revealed the need for a better reporting system. Future joint studies should be carried out between clinical and pharmacological departments to optimize communication and the correct use of medications in children.

A descriptive analysis of aspartate and alanine aminotransferase rise and fall following acetaminophen overdose

CONTEXT

Risk prediction following acetaminophen (paracetamol, APAP) overdose is based on serum APAP, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels. One recently proposed risk stratification tool, the APAPxAT multiplication product, uses either AST or ALT, whichever is higher, yet their interrelation is not well known following APAP-induced hepatic injury.

OBJECTIVE

To describe the kinetics of AST and ALT release into and disappearance from the circulation following APAP overdose.

MATERIALS AND METHODS

An observational case series of adult patients with peak AST or ALT > 100 IU/L attributable to APAP toxicity. Cases were identified by electronic search of hospital laboratory database and by discharge diagnosis corroborated by structured explicit medical record review.

RESULTS

Of 68 cases identified (mean age (SD): 39 (18) years, 63% female, and 21% ethanol co-ingested), 28 (41%) developed hepatotoxicity (peak AST or ALT > 1000 IU/L), 28 (41%) coagulopathy (international normalized ratio or INR > 2), and 21 (31%) both. Three patients (4%) were transferred for liver transplantation and ultimately six (8.8%) died. Serum AST and ALT activity rose in a closely aligned 1:1 AST:ALT ratio, but fell at distinctly different rates: AST activity fell with a half-life (interquartile range [IQR]) of 15.1 (12.2, 19.4) hours, and ALT 39.6 (32.9, 47.6) hours. Using an aminotransferase falling to below 50% of peak as the basis for discontinuing acetylcysteine would have resulted in antidotal treatment being stopped 24 (IQR: 9.6, 40) hours earlier (and in no cases later) using AST rather than ALT. Only six patients had an AST:ALT ratio greater than 2:1 at the time of acetylcysteine administration; of these six, four died and one survivor developed coagulopathy.

DISCUSSION

AST and ALT release into the circulation appears tightly linked and numerically similar, except in the sickest patients. Once the aminotransferases peak, AST returns to baseline more quickly.

CONCLUSION

Either AST or ALT can be used for early risk stratification tools when only one is known. Any criterion for N-AC discontinuation should be based on the decline of AST rather than ALT, with a potential benefit measured in days.

A comparison of non-fatal self-poisoning among males and females, in Sri Lanka

BACKGROUND

In the recent past Sri Lanka has had a high rate of attempted suicide by pesticide ingestion, among both males and females. Recent evidence suggests that these trends in self-poisoning may be changing, with increasing medicinal overdoses and changing gender ratios. In the past, attempted suicide in Sri Lanka has been described as impulsive acts, but research regarding aspects such as suicidal intent is limited, and there has been no comparison between genders. The objective of this study was to describe gender differences in non-fatal self-poisoning in Sri Lanka with respect to substances ingested, triggers, stressors, suicidal intent and psychiatric morbidity.

METHODS

Persons admitted to Teaching Hospital Peradeniya, Sri Lanka, for medical management of non-fatal self-poisoning over a consecutive 14-month period were eligible for the study. Participants were interviewed within one week of admission, with regard to demographic details, poison type ingested, triggers, psychiatric morbidity and suicidal intent. 949 participants were included in the study, of whom 44.2% were males, with a median age of 22 years.

RESULTS

Males were significantly more likely to ingest agrochemicals, whereas females were more likely to overdose on pharmaceutical drugs. Interpersonal conflict was a common trigger associated with non-fatal self-poisoning for both males and females. Alcohol use disorders and high suicidal intent were significantly more likely in males. There was no difference in rates of depression between the genders. Multiple regression for both genders separately showed that the presence of depression and higher levels of hopelessness was the strongest predictor of suicidal intent, for both genders.

CONCLUSIONS

Patterns of non-fatal self-poisoning in Sri Lanka appear to be changing to resemble Western patterns, with females having a greater rate of self-poisoning and more medicinal overdoses than males. Alcohol use disorder is a gender specific risk factor associated with non-fatal self-poisoning among males, indicating a need for specific intervention. However there are also many common risk factors that are common to both genders, particularly associations with interpersonal conflict as an acute trigger, and psychiatric morbidity such as depression and hopelessness being related to increased suicidal intent.

An investigation of one hundred suicides

Objectives: This study examines the backgrounds of 100 people who died by suicide and whose cases were adjudicated on consecutively over a five-year period, by the two Cork City coroners.

Method: Five main sources of information were used; coroners, relatives, investigating police, general practitioners and hospital records. The cases were examined under the headings of age and gender differences; methods used; social circumstances; illness; treatment prior to death and previous attempts. Certain information may have been missed because peers were not interviewed. There were 72 males and 28 females.

Results: In the 15-44 age group, the male female ratio was 4:1; in those over 45 the ratio was almost equal. Men were more likely to be unmarried even when age differences were taken into account. All the women and all but seven of the men had a psychiatric diagnosis, but women were more than more likely to have received medical treatment in the year before their suicide than men (OR = 6.6). Thirty-seven had made at least one previous suicide attempt.

Conclusions: The study confirms that suicide, particularly for men is becoming more a young person's problem. Psychiatric illness is the single commonest association. Over a third of suicides had made a previous attempt. These findings point to the need to improve recognition of psychological distress and find effective methods to reduce parasuicide.

A multicentre programme of clinical and public health research in support of the National Suicide Prevention Strategy for England

Objectives

To carry out a programme of linked research studies aimed at improving the management of self-harm, reducing the incidence of suicide and providing reliable data to evaluate the impact of theNational Suicide Prevention Strategy for England(2002).

Methods

There were four research streams: (1) we studied inquest records from 12 coroners and Ministry of Justice data to assess the accuracy of official suicide statistics; (2) we used Office for National Statistics mortality statistics, data from the Multicentre Study of Self-harm in England, national liver unit data, prescription data and patient interviews to assess (a) the impact of paracetamol (acetaminophen) pack size restrictions (1998), (b) the impact of withdrawal of co-proxamol in 2007 and (c) the relative toxicity in overdose of commonly used antidepressants; (3) we carried out 3-month audits of self-harm management in 32 hospitals to investigate variations between hospitals and the impact of management on repeat self-harm; and (4) we developed and piloted letter-based contact interventions aimed at reducing self-harm.

Key findings

(1) Between 1990 and 2005, the proportion of researcher-defined suicides given a verdict of suicide by the 12 coroners studied decreased by almost 7%, largely because of the increased use of misadventure/accident verdicts for deaths thought, on clinical review, to be suicides. Use of narrative verdicts increased markedly. Coroners who gave more narrative verdicts also gave fewer suicide verdicts, and geographical variations in the use of narrative verdicts appeared to distort reliable assessment of small-area differences in suicide rates. 2(a) UK legislation to reduce pack sizes of paracetamol was followed by a 43% reduction in number of deaths and a 61% reduction in registrations for liver transplantation over the next 11 years. Paracetamol overdoses were often impulsive and some were influenced by media (including the internet); sales outlets appeared mostly to be adhering to sales guidance. Smaller pack sizes of paracetamol for sale in Ireland compared with England did not result in a smaller number of tablets being taken in overdose. There was no clear evidence of an effect of the legislation on prescribing of non-steroidal anti-inflammatory drugs, nor on resulting gastrointestinal bleeds. 2(b) Withdrawal of co-proxamol from use in the UK resulted in approximately 600 fewer deaths than predicted between 2005 and 2010 based on previous trends, with no evidence of substitution by poisoning with other analgesics. 2(c) Of the tricyclic antidepressants, dosulepin and doxepin had the greatest toxicity. Citalopram was more toxic than other selective serotonin reuptake inhibitors. (3) There was marked variation between hospitals in the management of self-harm; effects of this variation on patient outcomes were unclear, although psychosocial assessment may have been associated with reduced repetition. Levels of specialist assessment remained static between 2001–2 and 2010–11, but service quality appeared to improve. (4) Findings of two pilot randomised controlled trials suggested that, although it would be feasible to scale up these interventions to full trials, these interventions might have low generalisability and be of limited benefit to patients.

Conclusion

Within the context of the strengths and limitations of the individual studies, this research programme has made significant additions to the evidence base related to suicide and self-harm prevention in the UK.

Study registration

A pilot study of a contact and information based intervention to reduce repeat self-harm; ISRCTN65171515.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Characteristics of non-fatal self-poisoning in Sri Lanka: a systematic review

Background

The rate of non-fatal self-poisoning in Sri Lanka has increased in recent years, with associated morbidity and economic cost to the country. This review examines the published literature for the characteristics and factors associated with non-fatal self-poisoning in Sri Lanka.

Methods

Electronic searches were conducted in Psychinfo, Proquest, Medline and Cochrane databases from inception to October 2011.

Results

26 publications (representing 23 studies) were eligible to be included in the review. A majority of studies reported non-fatal self-poisoning to be more common among males, with a peak age range of 10–30 years. Pesticide ingestion was the most commonly used method of non-fatal self-poisoning. However three studies conducted within the last ten years, in urban areas of the country, reported non-fatal self-poisoning by medicinal overdose to be more common, and also reported non-fatal self-poisoning to be more common among females. Interpersonal conflict was the most commonly reported short-term stressor associated with self-poisoning. Alcohol misuse was reported among males who self-poisoned, and data regarding other psychiatric morbidity was limited.

Conclusions

The findings indicate that pesticide ingestion is the commonest method of non-fatal self-poisoning in Sri Lanka, and it is more common among young males, similar to other Asian countries. However there appears to be an emerging pattern of increasing medicinal overdoses, paralleled by a gender shift towards increased female non-fatal self-poisoning in urban areas.

Many non-fatal self-poisoning attempts appear to occur in the context of acute interpersonal stress, with short premeditation, and associated with alcohol misuse in males. Similar to other Asian countries, strategies to reduce non-fatal self-poisoning in Sri Lanka require integrated intervention programs with several key aspects, including culturally appropriate interventions to develop interpersonal skills in young people, community based programs to reduce alcohol misuse, and screening for and specific management of those at high risk of repetition following an attempt of self-poisoning.

Long term effect of reduced pack sizes of paracetamol on poisoning deaths and liver transplant activity in England and Wales: interrupted time series analyses

OBJECTIVE

To assess the long term effect of United Kingdom legislation introduced in September 1998 to restrict pack sizes of paracetamol on deaths from paracetamol poisoning and liver unit activity.

DESIGN

Interrupted time series analyses to assess mean quarterly changes from October 1998 to the end of 2009 relative to projected deaths without the legislation based on pre-legislation trends.

SETTING

Mortality (1993-2009) and liver unit activity (1995-2009) in England and Wales, using information from the Office for National Statistics and NHS Blood and Transplant, respectively.

PARTICIPANTS

Residents of England and Wales.

MAIN OUTCOME MEASURES

Suicide, deaths of undetermined intent, and accidental poisoning deaths involving single drug ingestion of paracetamol and paracetamol compounds in people aged 10 years and over, and liver unit registrations and transplantations for paracetamol induced hepatotoxicity.

RESULTS

Compared with the pre-legislation level, following the legislation there was an estimated average reduction of 17 (95% confidence interval -25 to -9) deaths per quarter in England and Wales involving paracetamol alone (with or without alcohol) that received suicide or undetermined verdicts. This decrease represented a 43% reduction or an estimated 765 fewer deaths over the 11&frac14; years after the legislation. A similar effect was found when accidental poisoning deaths were included, and when a conservative method of analysis was used. This decrease was largely unaltered after controlling for a non-significant reduction in deaths involving other methods of poisoning and also suicides by all methods. There was a 61% reduction in registrations for liver transplantation for paracetamol induced hepatotoxicity (-11 (-20 to -1) registrations per quarter). But no reduction was seen in actual transplantations (-3 (-12 to 6)), nor in registrations after a conservative method of analysis was used.

CONCLUSIONS

UK legislation to reduce pack sizes of paracetamol was followed by significant reductions in deaths due to paracetamol overdose, with some indication of fewer registrations for transplantation at liver units during the 11 years after the legislation. The continuing toll of deaths suggests, however, that further preventive measures should be sought.

Low rates of hepatotoxicity among Asian patients with paracetamol overdose: a review of 1024 cases

Background

The metabolism of paracetamol in Asians is thought to differ from Westerners. Detailed clinical features of paracetamol -induced hepatotoxicity among Asians remains largely unreported.

Methods

A retrospective review of adult cases with paracetamol overdose over a five-year duration was performed in two of the largest public institutions in this country. Prevalence and predictive factors for hepatotoxicity were determined.

Results

Data on 1024 patients (median age 23 years, 82.0% female, ethnic groups: Malays 40.8%, Chinese 20.9% , Indian 33.2%) were obtained from January 2005 to December 2009. The median amount of paracetamol ingestion was 10.0 (IQR 5.0 - 15.0) g and the median serum paracetamol level was 274.80 (IQR 70.0 - 640.0) μmol/L at presentation. 75 (7.3%) patients developed hepatotoxicity. 23/ 55 (41.8%) patients who had ingested > 10 g of paracetamol and had a delayed (> 24 hour) administration of N-acetyl cystine (NAC) developed hepatotoxicity. No patients developed acute liver failure nor suffered any mortality (0%). Independent predictors for hepatotoxicity were identified as Malay (OR 2.22, 95% CI = 1.13-4.37) and Chinese (OR 3.26, 95% CI = 1.55-6.84) ethnicity, paracetamol dose > 10 g (OR 2.61, 95% CI = 1.53-4.46), prolonged duration of time from paracetamol ingestion to hospital presentation (> 24 hours OR 10.71, 95% CI = 3.46-33.15) and prolonged duration of time from paracetamol ingestion to NAC administration (> 24 hours OR 9.02, 95% CI = 2.97-27.45).

Conclusions

Paracetamol-induced hepatotoxicity rates in a multi-ethnic Asian population was low at 7.3%. Mortality and morbidity were non-existent despite high doses of paracetamol ingestion and delayed presentations to hospital.

Tramadol/paracetamol fixed-dose combination in the treatment of moderate to severe pain

Pain is the most common reason patients seek medical attention and pain relief has been put forward as an ethical obligation of clinicians and a fundamental human right. However, pain management is challenging because the pathophysiology of pain is complex and not completely understood. Widely used analgesics such as nonsteroidal anti-inflammatory drugs (NSAIDs) and paracetamol (acetaminophen) have been associated with adverse events. Adverse event rates are of concern, especially in long-term treatment or at high doses. Paracetamol and NSAIDs are available by prescription, over the counter, and in combination preparations. Patients may be unaware of the risk associated with high dosages or long-term use of paracetamol and NSAIDs. Clinicians should encourage patients to disclose all medications they take in a “do ask, do tell” approach that includes patient education about the risks and benefits of common pain relievers. The ideal pain reliever would have few risks and enhanced analgesic efficacy. Fixed-dose combination analgesics with two or more agents may offer additive or synergistic benefits to treat the multiple mechanisms of pain. Therefore, pain may be effectively treated while toxicity is reduced due to lower doses. One recent fixed-dose combination analgesic product combines tramadol, a centrally acting weak opioid analgesic, with low-dose paracetamol. Evidence-based guidelines recognize the potential value of combination analgesics in specific situations. The current guideline-based paradigm for pain treatment recommends NSAIDs for ongoing use with analgesics such as opioids to manage flares. However, the treatment model should evolve how to use low-dose combination products to manage pain with occasional use of NSAIDs for flares to avoid long-term and high-dose treatment with these analgesics. A next step in pain management guidelines should be targeted therapy when possible, or low-dose combination therapy or both, to achieve maximal efficacy with minimal toxicity.

Comparative drug dose and drug combinations in patients that present to hospital due to self-poisoning

Self-poisoning is a common reason for acute presentation to hospital. Commonly involved drugs have been reported, but few data exist concerning the different combinations of agents or comparative doses ingested. The present study sought to better characterise the typical patterns of drug overdose that may present via the emergency department. Consecutive adults ≥16 years of age that presented to York Hospital owing to self-poisoning were studied for 2010-2011 inclusive. The primary outcome measure was reported dose, expressed as a multiple of the defined daily dose (DDD) to allow comparison between different agents. There were 1024 patients, including 622 women (60.7%), and median age was 32 years (range, 16 to 92 years). Overdose in men was associated with a higher overall quantity of drugs: arithmetic mean of 20 DDD multiples (95% CI, 15-26) versus 13 (11-15), p = 0.001. Overdose involved a single agent only in 538 patients (52.5%). The mean paracetamol dose was 4.0 (95% CI, 3.7-4.3) DDD multiples; the doses of antidepressants (19.4, 17.0-21.7, p < 0.0001) and benzodiazepines (18.0, 12.8-23.2, p < 0.0001) were comparatively higher. The types of agents involved in self-poisoning and common combinations of agents are characterised. Psychotropic medications were ingested in comparatively larger quantities than analgesic agents and had worse clinical outcome. Further work is required to understand the factors that determine the quantity of drug ingested in patients at risk of drug overdose so as to minimise the risk of significant toxicity.

Reliability of the reported ingested dose of acetaminophen for predicting the risk of toxicity in acetaminophen overdose patients

PURPOSE

The present study examines the relationship between the dose of acetaminophen reported to have been ingested by patients and the occurrence of serum acetaminophen levels above the 'possible toxicity' line in patients presenting at the hospital after acetaminophen overdose. The prognostic value of patient-reported dosage cut-offs of 8, 10 and 12 g was determined.

METHODS

This retrospective cohort study included patients admitted to the emergency department or hospital within 24 hours of acetaminophen ingestion. Serum acetaminophen concentrations were considered to be the gold standard, and specificity, sensitivity and positive/negative predictive values were calculated from the reported ingested dose, to predict toxicity using the Rumack-Matthew nomogram (i.e. the 'possible toxicity' treatment line) and standard equations.

RESULTS

Of 305 patients identified, 291 met the study inclusion criteria, and 121 (41.6%) had serum acetaminophen concentrations above the 'possible toxicity' treatment line. The range of patient-reported acetaminophen ingested was 1-75 g, with 185 patients (63.6%) reporting ≥8 g. One hundred eighteen patients (97.5%) who reported ingesting ≥8 g had serum acetaminophen concentrations above the '150-line', compared with only three patients (2.5%) who reported ingesting <8 g (p < 0.001). The positive predictive value of a patient-reported dose ≥8 g for predicting serum acetaminophen concentrations above the 'possible toxicity' treatment line was 63.78%, with a negative predictive value of 97.17%. The sensitivity of patient-reported doses ≥8 g was high (97.52%) but with low specificity (60.59%). The sensitivity of patient-reported doses ≥10 g also was high (89.26%) with low specificity (65.29%), whereas the sensitivity of ≥12 g dose was low (61.16%) with high specificity (86.47%).

CONCLUSIONS

Patient-reported doses of acetaminophen are good risk indicators for acetaminophen overdose patients in Malaysia. Patient-reported ingestion of ≥8 g (as a cut-off dose) had a higher sensitivity than ≥10 g or ≥12 g. The results of this study have important implications for toxicity risk evaluations in areas with poor serum acetaminophen assay availability.

What can be done to reduce mortality from paracetamol overdoses? A patient interview study

BACKGROUND

Paracetamol (acetaminophen) is the most common self-poisoning agent in the UK and a leading cause of fatal hepatotoxicity. Following legislation in 1998 to limit pack sizes, beneficial effects on paracetamol-related mortality and morbidity were reported in England. However, there are still over 100 deaths a year and evidence of breaches of sales guidelines.

AIM

To investigate characteristics of people taking larger paracetamol overdoses and compliance with sales guidelines, to inform possible further initiatives to reduce paracetamol fatalities.

DESIGN AND METHODS

Interview study of 60 general hospital patients who took overdoses of over 16 paracetamol tablets (8 g).

RESULTS

Half of all paracetamol overdoses involved over 16 tablets. Patients were predominantly young (three-quarters aged 16-40 years) and female (58.3%); over half (53.3%) had taken a previous paracetamol overdose. Three-quarters said they wanted to die. Half took the overdose within an hour of first thinking of it, half (53.3%) took tablets already in the home and 58.3% bought tablets specifically for the overdose. Ten people tried to buy more than 32 tablets in one transaction; four succeeded. Most knew that a paracetamol overdose could cause death or permanent damage (88.3%) and harm the liver (80.0%) but 70.0% thought they would lose consciousness. Warnings on packs had little deterrent effect. Media and internet influences were identified. Patients chose paracetamol because it was cheap and easily available.

CONCLUSIONS

Further measures to reduce breaches of sales guidelines and the dangers of paracetamol overdose are required. Media and internet site producers should follow guidelines on reporting suicide.

Continuous multimechanistic postoperative analgesia: a rationale for transitioning from intravenous acetaminophen and opioids to oral formulations

Good surgical outcomes depend in part on good pain relief, allowing for early mobilization, optimal recovery, and patient satisfaction. Postsurgical pain has multiple mechanisms, and multimechanistic approaches to postoperative analgesia are recommended and may be associated with improved pain relief, lowered opioid doses, and sometimes a lower rate of opioid-associated side effects. Acetaminophen (paracetamol) is a familiar agent for treating many types of pain, including postsurgical pain. Oral acetaminophen has been shown to be safe and effective in a variety of acute pain models. Combination products using a fixed-dose of acetaminophen and an opioid have also been effective in treating postsurgical pain. Combination products with acetaminophen have demonstrated an opioid-sparing effect, which inconsistently results in a reduced rate of opioid-associated side effects. Intravenous (IV) acetaminophen and an opioid analgesic administered in the perioperative period may be followed by an oral acetaminophen and opioid combination in the postoperative period. Transitioning from an IV acetaminophen and opioid formulation to a similar but oral formulation of the same drugs appears to be a reasonable step in that both analgesic therapies are known to be safe and effective. For postsurgical analgesia with any acetaminophen product, patient education is necessary to be sure that the patient does not concurrently take any over-the-counter products containing acetaminophen and accidentally exceed dose limits.

Impact of different pack sizes of paracetamol in the United Kingdom and Ireland on intentional overdoses: a comparative study

Background

In order to reduce fatal self-poisoning legislation was introduced in the UK in 1998 to restrict pack sizes of paracetamol sold in pharmacies (maximum 32 tablets) and non-pharmacy outlets (maximum 16 tablets), and in Ireland in 2001, but with smaller maximum pack sizes (24 and 12 tablets). Our aim was to determine whether this resulted in smaller overdoses of paracetamol in Ireland compared with the UK.

Methods

We used data on general hospital presentations for non-fatal self-harm for 2002 - 2007 from the Multicentre Study of Self-harm in England (six hospitals), and from the National Registry of Deliberate Self-harm in Ireland. We compared sizes of overdoses of paracetamol in the two settings.

Results

There were clear peaks in numbers of non-fatal overdoses, associated with maximum pack sizes of paracetamol in pharmacy and non-pharmacy outlets in both England and Ireland. Significantly more pack equivalents (based on maximum non-pharmacy pack sizes) were used in overdoses in Ireland (mean 2.63, 95% CI 2.57-2.69) compared with England (2.07, 95% CI 2.03-2.10). The overall size of overdoses did not differ significantly between England (median 22, interquartile range (IQR) 15-32) and Ireland (median 24, IQR 12-36).

Conclusions

The difference in paracetamol pack size legislation between England and Ireland does not appear to have resulted in a major difference in sizes of overdoses. This is because more pack equivalents are taken in overdoses in Ireland, possibly reflecting differing enforcement of sales advice. Differences in access to clinical services may also be relevant.

Emergency department visits for overdoses of acetaminophen-containing products

BACKGROUND

Limited national data on the circumstances of acetaminophen overdoses have hindered identification and implementation of prevention strategies.

PURPOSE

To estimate the frequency of and characterize risks for emergency department visits for acetaminophen overdoses that were not related to abuse in the U.S.

METHODS

Data were collected from two components of the National Electronic Injury Surveillance System from January 1, 2006, through December 31, 2007, and analyzed from 2009 to 2010 to estimate the annual number of emergency department visits for non-abuse-related acetaminophen overdose by patient demographics, treatments, and type and amount of acetaminophen-containing product ingested.

RESULTS

There were an estimated 78,414 emergency department visits (95% CI=63655, 93172) annually for non-abuse-related overdoses of acetaminophen-containing products. Most emergency department visits for acetaminophen overdose were for self-directed violence (69.8%, 95% CI=66.4%, 73.2%), with the highest rate among patients aged 15-24 years (46.4 per 100,000 individuals per year). Unsupervised ingestions by children aged <6 years accounted for 13.4% (95% CI=11.0%, 15.9%) of visits for acetaminophen overdoses (42.5 per 100,000 individuals per year). Therapeutic misadventures accounted for 16.7% (95% CI=14.0%, 19.5%) of visits and most involved overuse for medicinal effects (56.1%, 95% CI=50.6%, 61.6%) rather than use of multiple acetaminophen-containing products or dose confusion.

CONCLUSIONS

Non-abuse-related overdoses of acetaminophen products lead to many emergency department visits each year, particularly emergency department visits for self-directed violence. Acetaminophen overdose prevention efforts will likely need to be multidimensional.

Detailed analyses of self-poisoning episodes presenting to a large regional teaching hospital in the UK

AIMS

The primary aim of this paper is to provide comprehensive contemporaneous data on the demographics, patterns of presentation and management of all episodes of deliberate self-poisoning presenting to a large regional teaching hospital over a 12 month period.

METHODS

We undertook detailed, retrospective analyses using information from electronic patient records and local patient-tracking, pathology and administrative databases. Statistical analyses were performed using Chi-squared tests, anova and two-tailed t-tests (Graphpad Prism).

RESULTS

One thousand five hundred and ninety-eight episodes of deliberate self-poisoning presented over the year. Demographic data and information on the month, day and time of admission are provided. 70.7% presented to the emergency department (ED) within 4 h of ingestion. 76.3% of patients had only one episode in an extended 29 month follow-up period. A mean of 1.72 drugs were taken per episode with just over half of all episodes involving a single drug only. Paracetamol and ibuprofen were the two most commonly ingested drugs involved in 42.5% and 17.3% of all overdoses respectively. 56.3% of patients taking paracetamol reported ingesting over 8 g (one over the counter packet). Detailed mapping of the patients' pathway through the hospital allowed an estimation of the hospital cost of caring for this patient group at pound 1.6 million pounds per year.

CONCLUSIONS

We present comprehensive and contemporary data on presentations to hospital resulting from deliberate self-poisoning. We include demographic information, presentation patterns, drugs used, a detailed analysis of episodes involving paracetamol and an estimate of the financial burden to hospitals of overdose presentations.

Limiting paracetamol pack size: has it worked in the UK?

INTRODUCTION

Paracetamol poisoning is a major health problem worldwide. Limitation of pack size is an approach increasingly advocated to reduce rates of suicide and serious self-harm from this agent. The United Kingdom adopted such a policy in 1998, restricting non-pharmacy sales to 8 g and pharmacy to pack sizes of 16 g.

METHODS

A literature review was conducted and commentary written on the impact of the change in the United Kingdom on a variety of indices of paracetamol overdose.

RESULTS

Potential markers of effect identified included paracetamol sales, poisons information data, laboratory results, liver unit referrals, and hospital activity and mortality data. Initial reports suggested effects associated with the legislation, but longer term suicide trend analysis has not confirmed these early findings, which were confounded by population trends in self-harm.

CONCLUSION

Paracetamol pack size limitation as applied in the United Kingdom has not reduced paracetamol-related death. Reasons postulated for this failure include patient avoidance of the legislation's intentions, patient confusion, and ineffectiveness of the regulations as conceived and implemented.

Is attempted suicide different in adolescent and adults?

Attempted suicide may be a different phenomenon in adolescents than in adults. To our knowledge, direct comparisons between these two populations are very scarce. The aim of this study is to analyze the differences between adolescents and adults in methods of attempted suicide, accompanying certainty of death, and intentionality. All cases admitted to one adult (n=173) and one adolescent (n=104) inpatient unit who attempted suicide in the period from January 2003 through October 2005 were included in a prospective, common, national register, with data on methods, circumstances, and intentionality. The methodology followed that of the WHO/Euro Multicenter Study on Parasuicide. A stratified analysis was performed using the Mantel-Haenszel procedure in order to control for the effects of gender and diagnosis. Adolescents used significantly more over-the-counter medicines. Adults were significantly more certain of the possible fatal outcome of their attempt and had a significantly more severe intention when harming themselves. Individuals appear to use the methods that are available to them to attempt suicide. Adolescents may display more impulsive and less lethal directed behavior than adults or, alternatively, they are more frequently admitted for less severe attempts.

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.

Impact of Restricting Paracetamol Pack Sizes on Paracetamol Poisoning in the United Kingdom

Paracetamol (acetaminophen) is the most common drug taken in overdose in the UK, accounting for 48% of poisoning admissions to hospital and being involved in an estimated 100-200 deaths per year. In 1998, the UK government introduced legislation that reduced the maximum pack size of all non-effervescent tablets and capsules containing aspirin (acetylsalicylic acid) or paracetamol that can be sold or supplied from outlets other than registered pharmacies from 25 to 16 tablets or capsules. This article reviews the literature to determine the effectiveness of the legislation, focusing specifically on paracetamol poisoning. Seventeen studies on this subject were identified. Three studies found reductions in mortality rates; one study found an increase in mortality rates, while one found an initial reduction followed by an eventual increase; three found no significant difference in mortality rates before and after introduction of the legislation. Five studies found reductions in admissions to liver units, three of these finding a reduction in liver transplantation rates; two further studies found no change in liver function tests and rates of paracetamol-induced acute liver injury or failure. Four studies found a sustained decrease in hospital admissions, while two found an initial decrease followed by an eventual increase. One study found a decline in admissions for paracetamol poisoning and an increase in admissions for non-paracetamol poisoning. Sales data are conflicting, with two studies finding no significant difference in paracetamol sales before and after the introduction of the legislation and one reporting a decline. The severity of overdose appears to have decreased since the maximum permitted packet size was reduced, with five studies reporting a reduction in the number of severe overdoses (measured by numbers of tablets ingested, serum paracetamol concentrations and usage of antidotes). Only two studies reported an increase in the number of severe overdoses.Paracetamol-associated mortality rates, admissions to liver units/liver transplants, hospital admissions and the severity of paracetamol overdose appear to have been decreasing since 1998. However, one study showed that the reductions in mortality and hospital admissions began in 1997; therefore, the contribution of the 1998 legislation to the observed changes is unclear. Most of the studies are based on short-term follow-up so it is difficult to draw any conclusions regarding long-term trends. Many of the studies were also restricted to relatively small areas of the UK; this, combined with a variety of outcome measures, makes it difficult to distinguish any conclusive trends. The studies also suffer from a lack of comparison and control groups. Some studies do not clearly differentiate between the paracetamol preparations covered by the legislation and those not. The limited number of studies to date, combined with a variety of outcome measures, make it difficult to determine with accuracy whether or not the legislation has been a success. More long-term studies are needed to fully assess the impact of the legislation.

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.

Choice of poison for intentional self-poisoning in rural Sri Lanka

BACKGROUND

Although intentional self-poisoning is a major public health problem in rural parts of the Asia-Pacific region, relatively little is known of its epidemiology. We aimed to determine why Sri Lankan self-poisoning patients choose particular poisons, and whether acts of self-harm with highly dangerous poisons were associated with more premeditation and effort.

METHODS

We interviewed 268 self-poisoning patients presenting to two district general hospitals in rural Sri Lanka.

RESULTS

Eighty-five percent of patients cited easy availability as the basis for their choice of poison. There was little premeditation: more than 50% ingested the poison less than 30 minutes after deciding to self-harm. Patients had little knowledge about treatment options or lethality of the poison chosen. We found no difference in reasons for choice of poison between people ingesting different poisons, despite marked differences in toxicity, and between people who died and those who survived.

CONCLUSIONS

Poisons were chosen on the basis of availability, often at short notice. There was no evidence that people using highly toxic poisons made a more serious or premeditated attempt. Restrictions on availability of highly toxic poisons in rural communities must be considered in strategies to reduce the number of intentional self-poisoning deaths in the Asia Pacific region.

Pain management today—what have we learned?

Pain is a leading cause of morbidity worldwide, with published data showing its prevalence as high as 50% for chronic pain in the European population. This prevalence is likely to continue to rise, particularly in elderly people with comorbid conditions and complex aetiologies of pain. There is thus a rapidly growing demand for safe and effective pain management. Management of mild-to-moderate pain has traditionally been based upon the use of non-steroidal anti-inflammatory drugs (NSAIDs) and the synthetic non-opioid analgesic paracetamol (acetaminophen), the latter of which acts centrally, inhibiting brain cyclo-oxygenase (COX) and nitric oxide synthase. Both the NSAIDs and paracetamol are effective for mild-to-moderate pain and are widely recommended and used. However, NSAIDs may not be tolerated due to gastrointestinal (GI) symptoms and can result in potentially fatal peptic ulceration and bleeding. Selective COX-2 inhibitors were developed to reduce the GI side effects and complications, but large-scale studies have highlighted another serious potential effect of anti-inflammatory drugs: cardiovascular events. Both the European Medicines Agency (EMEA) and the Food and Drugs Administration (FDA) in the US have issued advice to apply cautions and restrictions when prescribing COX-2 inhibitors, particularly for patients at increased cardiovascular risk and for long-term use. The FDA also applied cardiovascular warnings with regard to nonselective NSAIDs. Both the EMEA and the FDA have recommended using the lowest effective dose for the shortest duration. These concerns and warnings have left physicians seeking safe alternatives to anti-inflammatory drugs for both short- and long-term uses in many patients. These developments have generated a climate of uncertainty in the absence of official guidance on the selection of alternative analgesic regimens. Amongst the possible strategies, combinations of drugs that provide analgesic efficacy at reduced individual doses may confer the optimal risk-benefit ratio for pain management in the long term or in patients at increased cardiovascular risk. Weak opioids devoid of serious organ-damaging effects combined with paracetamol may well be safer for long-term therapy. Fixed-dose combinations of paracetamol with weak opioids, such as codeine, dextropropoxyphene or tramadol are currently available. Paracetamol plus tramadol is an effective and safe multimodal analgesic regimen for the management of both acute and chronic moderate-to-severe pain. Re-evaluating the role of weak opioids, such as tramadol, and combinations in pain management may prove a valuable option for prescribers seeking alternatives to anti-inflammatory drugs.

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.