Reducing paracetamol overdoses
BMJ 1996; 313 doi: https://doi.org/10.1136/bmj.313.7070.1417 (Published 07 December 1996) Cite this as: BMJ 1996;313:1417- Elizabeth Fagan,
- Gary Wannan
- Professor Section of Hepatology, Rush Presbyterian St Luke's Medical Center, Chicago, Illinois 60612, USA
- Senior house officer Maudsley Hospital, London, SE5 8AZ
More likely to succeed through public education than package labelling
Medicines containing paracetamol (acetaminophen) are the commonest cause of intentional drug overdose in Britain1 2 3 4 and are increasingly implicated elsewhere in Europe3 and the United States. Around 70 000 cases of paracetamol overdose occur annually in Britain, and numbers are growing.4 Fortunately, death from overdose is rare—about 200 cases a year in Britain—against a remarkable safety record of 30 million packs containing paracetamol sold each year.1 2 3 4 Hospital resources have been concentrated on trying to anticipate the few patients most likely to develop serious liver injury after overdose5 6 since many deaths are preventable by early intervention, including treatment with the antidote N-acetylcysteine.5 6 A bigger problem, however, is how to predict who is going to take an overdose and how to stop them.
Last month, Britain's Medicines Control Agency launched a programme of consultation on the availability of solid dose analgesics, including paracetamol.7 The aim is to reinforce the safe use of paracetamol. The programme proposes the inclusion of warnings about overdose in the product information statements, including the risk of serious liver damage from overdose and the need to seek immediate medical advice even if well. Current statements must declare the presence of paracetamol and include warnings not to exceed the stated dose and to consult a doctor if symptoms persist.
The Medicines Control Agency is also seeking views on limiting individual general sales of products containing paracetamol to 6 g for adults and 1.44 g for children—typically 12 tablets or capsules—and for pharmacy sales not to exceed 30 and 100 tablets for short and long term conditions respectively.7 In announcing the programme of consultation, Gerald Malone, minister of health, stated that “the way forward is to ensure that full and accurate information reaches consumers, that information should be conveyed both on the label and patient leaflet, in a pack whose size meets their needs without leaving large numbers in the bathroom cabinet.”
The success of these proposals, if they are carried, will depend largely on their success in deterring those most likely to take overdoses. The difficulty lies in reaching this target population. Most overdoses in Britain seem to result from impulsive acts.1 2 3 4 Those who seek manipulative gain, especially adolescents, favour paracetamol for self poisoning. Paracetamol has replaced other drugs, such as aspirin, as a popular choice for pain relief and, consequently, for overdose because selection is dictated by ready availability, sales, and prescription rates.2 8 9 Studies from Oxford show that, although most people who overdose know that paracetamol can be dangerous, prior knowledge of potential death and warnings on labels, however shocking, were deterrents in only a quarter of patients interviewed.1 2 4
Restricting individual sales should affect the number of serious overdoses, although this is not entirely predictable.9 In France, where packet size is limited to 8 g, overdose is common but severe hepatotoxicity and death are rare.10 However, of people in Oxford who took more than 12 tablets, only 37% said that they would have taken smaller quantities had their packets been limited to 12 tablets.4 The effect of blister packs is also uncertain. Although people using them were less likely than people using loose supplies to take more than 25 tablets (40% compared to 60%), the amount ingested reflected immediate availability.4 The ever increasing number of formulations containing paracetamol poses practical problems for deterrent packaging, and, anyway, the new proposals on limiting pack size do not extend to effervescent tablets, granules, and sachets.7
Recommendations to limit the availability of designated drugs by reducing pack size or making larger amounts available only on prescription may reduce the number of serious overdoses. But given the impulsive nature of overdose, they are unlikely to reduce the total number of overdoses. The extra investment costs, if passed to the consumer, would seem an unfair financial penalty for the millions who heed recommended doses. Furthermore, selective restrictions could favour overdose with the next most available drug, or “cocktails” of unknown formulations and inferior safety record to that of paracetamol.
While we endorse the need to encourage consumers to read and heed drug safety information, we remain unconvinced, as do others,4 about the likely impact of any form of warnings on labels and packets as a deterrent to overdose, especially among those who seek manipulative gain. We recommend disseminating public safety information about all the popular drugs through educational programmes in schools and via additional media such as television, radio, newspapers, and even the Internet. Information should encourage early hospital treatment after overdose, emphasising for paracetamol the high efficacy of the antidote.6 Any campaign that publicises the toxicity of specific drugs should be monitored carefully to watch for increases in selection of other drugs.