Safety packaging of acetaminophen combination preparations and severity of adult poisoning

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.

Acute liver failure

Worldwide, viral hepatitis is the leading cause of acute liver failure, whereas acetaminophen hepatotoxicity is the most commonly identified cause in Western countries. Restricting the quantity of acetaminophen tablets dispensed has been shown to reduce morbidity and mortality in countries with a high incidence of acetaminophen overdose. Troglitazone and bromfenac are two recently approved medications that were withdrawn from the market due to an unacceptably high incidence of severe hepatotoxicity. In addition, trovafloxacin, nefazodone, and ritonavir were reported to be associated with severe hepatitis and acute liver failure. Moderate hypothermia is a simple and potentially effective means of reducing intracranial pressure in patients with acute liver failure and cerebral edema. However, controlled clinical trials are needed to determine proper patient selection and optimize treatment. Extracorporeal bioartificial liver support devices remain an exciting but as yet unproven means of supporting acute liver failure patients with advanced encephalopathy. Living donor liver transplantation has recently been reported for adults and children with acute liver failure. However, ethical concerns regarding donor safety and the ability to obtain informed consent without coercion have been raised. Lastly, advances in the identification and isolation of pluripotent liver stem cells in human bone marrow provides hope for a simple and effective means of enhancing native liver regeneration.

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

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

Poisoning and epidemiology: 'toxicoepidemiology'

1. There is little hypothesis-testing clinical research performed in toxicology. Randomized clinical trials are rare and most observational studies are performed on highly selected patients and are subject to marked bias. Thus, for many poisonings, our approach has been based almost entirely on deduction from known pharmacological/toxicological effects, generalizations from drugs within the same therapeutic class, animal data and case reports. This is also far from satisfactory, as many toxicological mechanisms are poorly understood and not related to the therapeutic class. 2. Although we need much better data to address the clinical and public health aspects of poisoning, there are many practical and ethical reasons why randomized clinical trials are difficult in this field. However, the scope for observational research, in particular population-based clinical epidemiology, is almost unlimited. The collection of data on human poisoning is facilitated because most non-fatal overdoses are admitted to hospital and by legal requirements to report to the coroner deaths that are due to poisoning. In the present article I argue that 'toxicoepidemiology', meaning the application of epidemiological methods to the problem of acute poisoning, is the best means we have of addressing deficiencies in our knowledge of poisoning. 3. Examples are given of a variety of observational research strategies, ranging from audit to meta-analysis, that may be applied to clinical toxicology. From coronial and clinical data obtained from reasonably well-defined populations, it has been possible to identify a number of previously unrecognized differences in the severity and spectrum of toxicity between and within drug classes. Also, the demographic risk factors for poisoning and the reproducibility, validity and optimal use of diagnostic and therapeutic interventions can be assessed. 4. The major limitations to the range of associations and interventions that may be studied are the need to achieve adequate power to study uncommon outcomes or poisonings and the ability to replicate findings at other centres using similar methodology. The expansion of data collection to other centres has the potential largely to overcome these obstacles.