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

The use of implementation science theories, models, and frameworks in implementation research for medicinal products: A scoping review

BACKGROUND

The uptake, adoption and integration of new medicines and treatment regimens within healthcare delivery can take a decade or more. Increasingly, implementation science (IS) research is being used to bridge this gap between the availability of new therapeutic evidence and its actual application in clinical practice. Little is known, however, about the quality of IS research in this area, including the degree to which theories, models and frameworks (TMFs) are being used. The objective of this study was to conduct a scoping review of the use of TMFs in implementation research involving medicinal products.

METHODS

A search was conducted for English language abstracts and manuscripts describing the application of TMFs in IS studies for medicinal products. Eligible publications were those published between 1 January 1974 and 12 December 2022. All records were screened at the title and abstract stage; included full-text papers were abstracted using data extraction tables designed for the study. Study quality was appraised using the Implementation Research Development Tool.

RESULTS

The initial scoping search identified 2697 publications, of which 9 were ultimately eligible for inclusion in the review. Most studies were published after 2020 and varied in their objectives, design and therapeutic area. Most studies had sample sizes of fewer than 50 participants, and all focused on the post-marketing phase of drug development. The TMF most frequently used was the Consolidated Framework for Implementation Research (CFIR). Although most studies applied all TMF domains, TMF use was limited to instrument development and/or qualitative analysis. Quality appraisals indicated the need for engaging patients and other stakeholders in the implementation research, reporting on the cost of implementation strategies, and evaluating the unintended consequences of implementation efforts.

CONCLUSIONS

We found that few IS studies involving medicinal products reported using TMFs. Those that did encompassed a wide variety of therapeutic indications and medicinal products; all were in the post-marketing phase and involved limited application of the TMFs. Researchers should consider conducting IS in earlier phases of drug development and integrating the TMFs throughout the research process. More consistent and in-depth use of TMFs may help advance research in this area.

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.

Restriction of non-opioid analgesics sold over-the-counter in Denmark: A national study of impact on poisonings

OBJECTIVE

Self-poisoning with non-opioid analgesics presents a growing challenge to health care providers. We aimed to assess the impact of an 18-year age restriction of OTC sales and a pack size restriction of non-opioid analgesics sold OTC in pharmacies on hospital-treated poisonings and poisoning severity measured using biomarkers.

METHODS

We applied a before and after design using interrupted time series analysis. Data on all poisonings recorded as hospital admissions were obtained during 2002-2015 and biochemical parameters from laboratory databases during 2011-2015, both covering the entire Danish population.

RESULTS

The age restriction was followed by a 17% level reduction in admissions for non-opioid analgesic poisoning among young people age 10-17 years (RR 0.830; 95% CI 0.697-0.988; p < 0.036). After the pack size restriction, an instant level reduction of 18.5% (RR 0.815; 95% CI 0.729-0.912; p < 0.001) was observed for the entire population. A 27% decrease in the number of poisonings with alanine transaminase levels (ALT) ≥ 210 U/L was observed (RR 0.734; 95% CI 0.579-0.931; p = 0.011) followed by 40% decrease in biomarkers indicative of liver failure (RR 0.597; 95% CI 0.421-0.847; p = 0.004). We also observed similar reductions for other poisonings such as psychotropics.

LIMITATIONS

Although declines in poisonings were observed after implementation of means restrictive measures, a causal link cannot be inferred.

CONCLUSION

Age and pack size restriction were assiociated with a reduction in the numbers of poisonings. This was also observed for pharmaceutical poisonings in general, which might suggest a non-specific or spill-over effect.

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.

Evaluation of a Food and Drug Administration Mandate to Limit Acetaminophen in Prescription Combination Products

INTRODUCTION

In 2014, the US Food and Drug Administration limited the production of prescription acetaminophen-opioid combination products to 325 mg per dose unit. The goal of this mandate was to decrease the likelihood of unintentional acetaminophen hepatotoxicity. This study was designed to determine if this federal regulation has succeeded in reducing unintentional acetaminophen-induced hepatotoxicity from opioid combination products.

METHODS

Using data from the National Poison Data System (NPDS), we analyzed all calls to US Poison Control Centers in the years 2013 and 2015 for acetaminophen-opioid combination product exposures. We then excluded cases that were classified as intentional and those aged 12 years and younger. We used a primary endpoint of N-acetylcysteine administration; secondary endpoints included evidence of hepatotoxicity as aspartate aminotransferase elevation, opioid antagonist administration and severity of overall medical outcome.

RESULTS

A total of 18,259 calls between the two yearlong periods met inclusion criteria. 5.16 and 5.01% of calls resulted in N-acetylcysteine administration in 2013 and 2015, respectively. 3.63 and 4.02% received naloxone in 2013 and 2015, respectively, and 0.9% in each year developed hepatotoxicity. Rates of N-acetylcysteine administration, naloxone administration, and hepatotoxicity did not differ significantly between 2013 and 2015. Severity of medical outcome was worse in 2015 as compared to 2013 with more cases being categorized as "major effect" and fewer cases being categorized as "no effect."

CONCLUSIONS

The Food and Drug Administration limitation on acetaminophen content per dose unit in opioid combination products did not reduce the occurrence of unintentional acetaminophen-induced hepatotoxicity or N-acetylcysteine administration as reported to NPDS.

[Prescription of acetaminophen in five French hospitals: What are the practices?]

AIM

Acetaminophen is widely used in hospital settings and often considered as nontoxic. We conducted a multicentric study in order to evaluate its proper use.

METHOD

Prescriptions from five general hospitals were analyzed, according to dose adjustments required in renal or liver failure, weight or chronic alcoholism, determined using a literature review. Other criteria have been assessed: indication for parenteral access, accuracy of administration time and pain assessment.

RESULTS

Among the 1256 analyzed prescriptions, 21% are non-compliants. The main causes of non-compliance (NC) are adjustments to weight and renal failure. Higher NC rates concern chronic alcoholism and liver failure.

CONCLUSION

Misuse of acetaminophen seems related to a lack of official recommendations concerning dose adjustments. Hospital pharmacists have an important role to play in the promotion of proper use of acetaminophen. Therefore we established a prescribing aid.

Pack size and paracetamol overdose: 16 years later

In 1998 the United Kingdom limited the availability of paracetamol sold over-the-counter in an effort to reduce serious paracetamol overdose. Since that time debate has continued on the effectiveness of this policy in reducing what is acknowledged as a major public health problem. This commentary reviews recent publications on this topic which suggest that the effects were small. Reasons for this are discussed using data from recent work.

Reducing a suicidal person's access to lethal means of suicide: a research agenda

Reducing the availability of highly lethal and commonly used suicide methods has been associated with declines in suicide rates of as much as 30%-50% in other countries. The theory and evidence underlying means restriction is outlined. Most evidence of its efficacy comes from population-level interventions and natural experiments. In the U.S., where 51% of suicides are completed with firearms and household firearm ownership is common and likely to remain so, reducing a suicidal person's access to firearms will usually be accomplished not by fiat or other legislative initiative but rather by appealing to individual decision, for example, by counseling at-risk people and their families to temporarily store household firearms away from home or otherwise making household firearms inaccessible to the at-risk person until they have recovered. Providers, gatekeepers, and gun owner groups are important partners in this work. Research is needed in a number of areas: communications research to identify effective messages and messengers for "lethal means counseling," clinical trials to identify effective interventions, translational research to ensure broad uptake of these interventions across clinical and community settings, and foundational research to better understand method choice and substitution. Approaches to suicide methods other than firearms are discussed. Means restriction is one of the few empirically based strategies to substantially reduce the number of suicide deaths.

The epidemiology and management of adult poisonings admitted to the short-stay ward of a large Scottish emergency department

BACKGROUND AND AIMS

The emergency department of Aberdeen Royal Infirmary receives around 68,000 new adult admissions annually. All poisoning cases are admitted to a 14-bedded short-stay ward, except those admitted to intensive care or immediately discharged. This study aimed to analyse epidemiological trends and management of short-stay ward admissions for poisonings.

METHOD AND RESULTS

Adult (>13 years) poisoning presentations admitted to the emergency department short-stay ward of Aberdeen Royal Infirmary from 1 January-31 December 2009 were retrospectively reviewed using patient discharge summaries. During 2009, there were 1062 poisoning cases, of which repeat episodes were responsible for 15%. The mean age of presentation was 33.9 years (SD 14.4) and there was a female preponderance (62%). Almost half of poisonings were polypharmacy, alcohol was involved in 40% of cases and overdoses most commonly involved paracetamol (43%). Management involved basic observations only (66%), N-acetylcysteine (24%), naloxone (4%) and activated charcoal (1%). Liaison psychiatry reviewed 84% presentations and admitted 9% to the psychiatric unit.

CONCLUSIONS

The short-stay ward is important for acute management of poisonings and the data gained from this study should help to direct patient services appropriately.

Suicides by jumping from a height in Hong Kong: a review of coroner court files

PURPOSE

Jumping from a height is the most common method for suicide in Hong Kong and other urban cities, but it remains understudied locally and internationally. We used Coroner records in exploring the ecological factors associated with these deaths and the personal characteristics of persons who jumped to their death (hereafter, "jumping suicides"). We compared suicides by jumping with all other suicides and examined the suicides that occurred at ten different jumping sites.

METHODS

The Coroner's files of all suicides in Hong Kong from 2002 to 2007 included 6,125 documented deaths.

RESULTS

2,964 (48.4%) involved jumping during the study period. Eighty-three percent (83%) of suicide jumps occurred in residential buildings, and of these, 61% occurred from the decedent's own home. Jumping suicides differed from non-jumping suicides in terms of their socio-demographic characteristics (e.g., for male: 60.8 vs. 67.3% of jumping suicide and non-jumping suicides, p < 0.0001) and the presence of physical illness (44.4 vs. 42.7% for jumping and non-jumping suicides, p < 0.0001). While statistically significant, these differences are relatively modest. In contrast, 40.7 documented illnesses vs. 23.1% for jumping and non-jumping suicides (p < 0.0001).

CONCLUSIONS

Means restriction is a key strategy for suicide prevention. Installation of physical barriers, one of the mean restriction strategies, at common places for suicide has strong evidence to avert suicides without substitution effects. There seems to be challenges to implement physical barriers to prevent residential jumping suicides. Simply applying physical barriers to preclude jumping in Hong Kong appears to be difficult given its ubiquitous "high-rise" residential dwellings. Hence, we also need to develop alternative strategies aimed at preventing people from becoming suicidal.

Characterizing suicide in Toronto: an observational study and cluster analysis

OBJECTIVE

To determine whether people who have died from suicide in a large epidemiologic sample form clusters based on demographic, clinical, and psychosocial factors.

METHOD

We conducted a coroner's chart review for 2886 people who died in Toronto, Ontario, from 1998 to 2010, and whose death was ruled as suicide by the Office of the Chief Coroner of Ontario. A cluster analysis using known suicide risk factors was performed to determine whether suicide deaths separate into distinct groups. Clusters were compared according to person- and suicide-specific factors.

RESULTS

Five clusters emerged. Cluster 1 had the highest proportion of females and nonviolent methods, and all had depression and a past suicide attempt. Cluster 2 had the highest proportion of people with a recent stressor and violent suicide methods, and all were married. Cluster 3 had mostly males between the ages of 20 and 64, and all had either experienced recent stressors, suffered from mental illness, or had a history of substance abuse. Cluster 4 had the youngest people and the highest proportion of deaths by jumping from height, few were married, and nearly one-half had bipolar disorder or schizophrenia. Cluster 5 had all unmarried people with no prior suicide attempts, and were the least likely to have an identified mental illness and most likely to leave a suicide note.

CONCLUSIONS

People who die from suicide assort into different patterns of demographic, clinical, and death-specific characteristics. Identifying and studying subgroups of suicides may advance our understanding of the heterogeneous nature of suicide and help to inform development of more targeted suicide prevention strategies.

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.

Installation of a bridge barrier as a suicide prevention strategy in Montréal, Québec, Canada

OBJECTIVES

We investigated whether the installation of a suicide prevention barrier on Jacques-Cartier Bridge led to displacement of suicides to other jumping sites on Montréal Island and Montérégie, Québec, the 2 regions it connects.

METHODS

Suicides on Montréal Island and Montérégie were extracted from chief coroners' records. We used Poisson regression to assess changes in annual suicide rates by jumping from Jacques-Cartier Bridge and from other bridges and other sites and by other methods before (1990-June 2004) and after (2005-2009) installation of the barrier.

RESULTS

Suicide rates by jumping from Jacques-Cartier Bridge decreased after installation of the barrier (incidence rate ratio [IRR] = 0.24; 95% confidence interval [CI] = 0.13, 0.43), which persisted when all bridges (IRR = 0.39; 95% CI = 0.27, 0.55) and all jumping sites (IRR = 0.66; 95% CI = 0.54, 0.80) in the regions were considered.

CONCLUSIONS

Little or no displacement to other jumping sites may occur after installation of a barrier at an iconic site such as Jacques-Cartier Bridge. A barrier's design is important to its effectiveness and should be considered for new bridges with the potential to become symbolic suicide sites.

Internet survey of home storage of paracetamol by individuals in the UK

AIM

Paracetamol (acetaminophen) is a common cause of liver failure due to overdose. Legislation introduced in the UK in 1998 to limit pack sizes of paracetamol has had limited impact on the overall number and severity of paracetamol overdoses. This may be because people have large amounts of paracetamol stored at home, but no previous studies have explored this question.

METHODS

Individuals who regularly take part in market research surveys were invited to take part in an Internet survey. They were asked to supply demographic details, the frequency with which they use paracetamol and ibuprofen, and details of the amount and location of these drugs that they possessed.

RESULTS

The mean age of respondents was 43.3 years (standard deviation 14.5 years), and 49.9% were female. People with both ibuprofen and paracetamol tended to have more packs and tablets of paracetamol (P < 0.001) and over a third had 32 or more paracetamol tablets. The most common pack size was 16 tablet packs (44.8% of all packs), which accounted for 39.4% of tablets. The most common site of paracetamol storage in the home was the kitchen (63.8% of people, 95% confidence interval 60.7, 66.7).

CONCLUSION

This study suggests that pack size legislation in the UK has had limited effect on the amount of paracetamol that individuals have access to in the home. This may explain, at least in part, the limited impact of the pack size legislation on paracetamol overdoses in the UK.

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.

Means restriction for suicide prevention

Limitation of access to lethal methods used for suicide--so-called means restriction--is an important population strategy for suicide prevention. Many empirical studies have shown that such means restriction is effective. Although some individuals might seek other methods, many do not; when they do, the means chosen are less lethal and are associated with fewer deaths than when more dangerous ones are available. We examine how the spread of information about suicide methods through formal and informal media potentially affects the choices that people make when attempting to kill themselves. We also discuss the challenges associated with implementation of means restriction and whether numbers of deaths by suicide are reduced.

Substances used in completed suicide by overdose in Toronto: an observational study of coroner's data

OBJECTIVE

To identify the substances used by people who die from suicide by overdose in Toronto and to determine the correlates of specific categories of substances used.

METHOD

Coroner's records for all cases of suicide by overdose in Toronto, Ontario, during a 10-year period (1998 to 2007) were examined. Data collected included demographic data, all substances detected, and those determined by the coroner to have caused death. Logistic regression analyses were used to examine demographic and clinical factors associated with suicide by different drug types.

RESULTS

There were 397 documented suicides by overdose (mean age 49.1 years, 50% female). Most substances detected were psychotropic prescription medications (n = 245), followed by other prescription medications (n = 143) and over-the-counter (OTC) medications (n = 83). More than one-half of all suicides by overdose were determined to have only one specific substance as the cause of death (n = 206). In suicides where only one class of substance was present in lethal amounts, OTC medication (n = 48), opioid analgesics (n = 44), and tricyclic antidepressants (n = 44) were most common.

CONCLUSIONS

Suicides by overdose involved the use of different classes of substances, including psychotropic prescription medication, other prescription medications, as well as OTC medications. Physicians and pharmacists should be aware of commonly used prescription and OTC medications in overdose and exercise increased vigilance in prescribing or dispensing them to at-risk patients.

Controlling access to suicide means

Background: Restricting access to common means of suicide, such as firearms, toxic gas, pesticides and other, has been shown to be effective in reducing rates of death in suicide. In the present review we aimed to summarize the empirical and clinical literature on controlling the access to means of suicide. Methods: This review made use of both MEDLINE, ISI Web of Science and the Cochrane library databases, identifying all English articles with the keywords “suicide means”, “suicide method”, “suicide prediction” or “suicide prevention” and other relevant keywords. Results: A number of factors may influence an individual’s decision regarding method in a suicide act, but there is substantial support that easy access influences the choice of method. In many countries, restrictions of access to common means of suicide has lead to lower overall suicide rates, particularly regarding suicide by firearms in USA, detoxification of domestic and motor vehicle gas in England and other countries, toxic pesticides in rural areas, barriers at jumping sites and hanging, by introducing “safe rooms” in prisons and hospitals. Moreover, decline in prescription of barbiturates and tricyclic antidepressants (TCAs), as well as limitation of drugs pack size for paracetamol and salicylate has reduced suicides by overdose, while increased prescription of SSRIs seems to have lowered suicidal rates. Conclusions: Restriction to means of suicide may be particularly effective in contexts where the method is popular, highly lethal, widely available, and/or not easily substituted by other similar methods. However, since there is some risk of means substitution, restriction of access should be implemented in conjunction with other suicide prevention strategies.

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.

Do local landmark bridges increase the suicide rate? An alternative test of the likely effect of means restriction at suicide-jumping sites

A number of recent studies have examined the effect of installing physical barriers or otherwise restricting access to public sites that are frequently used for suicides by jumping. While these studies demonstrate that barriers lead to a reduction in the number of suicides by jumping at the site where they are installed, thus far no study has found a statistically significant reduction in the local suicide rate attributable to a barrier. All previous studies are case studies of particular sites, and thus have limited statistical power and ability to control for confounding factors, which may obscure the true relationship between barriers and the suicide rate. This study addresses these concerns by examining the relationship between large, well-known bridges ("local landmark" bridges) of the type that are often used as suicide-jumping sites and the local suicide rate, an approach that yields many more cases for analysis. If barriers at suicide-jumping sites decrease the local suicide rate, then this implies that the presence of an unsecured suicide-jumping site will lead to a higher local suicide rate in comparison to areas without such a site. The relationship between suicides and local landmark bridges is examined across 3116 US counties or county equivalents with negative binomial regression models. I found that while exposure to local landmark bridges was associated with an increased number of suicides by jumping, no positive relationship between these bridges and the overall number of suicides was detected. It may be impossible to conclusively determine if barriers at suicide-jumping sites reduce the local suicide rate with currently available data. However, the method introduced in this paper offers the possibility that better data, or an improved understanding of which potential jumping sites attract suicidal individuals, may eventually allow researchers to determine if means restriction at suicide-jumping sites reduces total suicides.

FDA proposals to limit the hepatotoxicity of paracetamol (acetaminophen): are they reasonable?

Hepatotoxicity from paracetamol is of great concern because of the considerable number of patients who develop severe toxicity from this drug. A group of senior medical practitioners, academics and scientists were brought together on June 29 and 30, 2009 by the Food and Drug Administration of USA (FDA) with the aim of providing advice on how to limit the number of cases of hepatotoxicity due to paracetamol in USA. The most contentious recommendations were the reduction in the dose of paracetamol to 650 mg and the elimination of prescription combination products of paracetamol and opiates. The first recommendation indicates that many members of the committee consider, despite much evidence to the contrary, that therapeutic doses of paracetamol (up to 4 g daily) are associated with a significant incidence of hepatotoxicity. The second recommendation, if accepted by FDA, will require major changes in the therapeutic use of paracetamol and opiates. Adoption of these two recommendations may lead to the increased use of NSAIDs with the potential of increasing incidence of NSAIDs-related adverse reactions.

The FDA Acetaminophen Advisory Committee Meeting - what is the future of acetaminophen in the United States? The perspective of a committee member

BACKGROUND

Unintentional acetaminophen toxicity is a common problem throughout the world but particularly in the more developed countries. To deal with the problem, several countries have attempted to decrease the risk of acetaminophen overdose by reducing package sizes. The U.S. Food and Drug Administration (FDA) convened a joint meeting recently of three Advisory Committees to consider the issue of unintentional acetaminophen-related toxicity and to explore strategies to address the problem.

PROPOSALS AND RECOMMENDATIONS

Three strategies addressed the issue of dose reduction as a way to decrease morbidity and mortality. The FDA proposed a decrease in the maximum daily dose from 4,000 to 3,250 mg, reducing the maximum individual dose from 1,000 to 650 mg and relegating 500 mg tablets to prescription status. The Committees voted in favor of each of those initiatives. Restricting the number of doses that could be purchased by regulating package sizes, as has been done in some European countries, was proposed, but rejected by the Committees. Proposals also addressed the elimination of nonprescription and prescription acetaminophen combination products (e.g., multi-symptom cold relief combinations and acetaminophen/opioid combinations) as a strategy to decrease unintentional poisoning when individuals unknowingly take different products, all of which contain acetaminophen. The Committees rejected the proposal to eliminate the nonprescription combinations but recommended the elimination of prescription combination products. Currently, liquid acetaminophen is available in the United States in three different concentrations. To reduce the confusion associated with the variance in concentrations the Committees voted to have a single concentration for all acetaminophen liquid products. Finally, the Committees voted, almost unanimously, to encourage the FDA to place a boxed warning in the product information to create awareness among prescribers and pharmacists about acetaminophen toxicity and to educate their patients accordingly.

CONCLUSIONS

Many of the recommendations were not evidence-based but instead have an anecdotal basis. However, the Committees are advisory to the FDA, their recommendations are not binding and it remains to be seen which of the recommendations will be implemented.