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

Abstract
Objective: To evaluate the effects on suicidal behaviour of legislation limiting the size of packs of paracetamol and salicylates sold over the counter. Setting: UK population, with detailed monitoring of data from five liver units and seven general hospitals, between September 1996 and September 1999. subjects: People who died by suicidal or accidental overdose with paracetamol or salicylates, or who died of undetermined causes; patients admitted to liver units with hepatic paracetamol poisoning; patients presenting to general hospitals with self poisoning after taking paracetamol or salicylates. Main outcome measures: Mortality from paracetamol or salicylate overdose; numbers of patients referred to liver units or listed for liver transplant; numbers of transplantations; numbers of overdoses and tablets taken; blood concentrations of the drugs; prothrombin times; sales to pharmacies and other outlets of paracetamol and salicylates. Results: Numbers of tablets per pack of paracetamol and salicylates decreased markedly in the year after the change in legislation on 16 September 1998. The annual number of deaths from paracetamol poisoning decreased by 21% (95% confidence interval 5% to 34%) and the number from salicylates decreased by 48% (11% to 70%). Liver transplant rates after paracetamol poisoning decreased by 66% (55% to 74%). The rate of non-fatal self poisoning with paracetamol in any form decreased by 11% (5% to 16%), mainly because of a 15% (8% to 21%) reduction in overdoses of paracetamol in non-compound form. The average number of tablets taken in paracetamol overdoses decreased by 7% (0% to 12%), and the proportion involving >32 tablets decreased by 17% (4% to 28%). The average number of tablets taken in salicylate overdoses did not decrease, but 34% fewer (2% to 56%) salicylate overdoses involved >32 tablets. After the legislation mean blood concentrations of salicylates after overdose decreased, as did prothrombin times; mean blood concentrations of paracetamol did not change. Conclusion: Legislation restricting pack sizes of paracetamol and salicylates in the United Kingdom has had substantial beneficial effects on mortality and morbidity associated with self poisoning using these drugs. What is already known on this topic Paracetamol and salicylate overdoses are very common in the United Kingdom and are associated with high levels of mortality and morbidity International comparison shows that national mortality from paracetamol overdose may be related to the maximum number of tablets in individual preparations Legislation to limit the size of packs of paracetamol and salicylates was introduced in the United Kingdom in September 1998 What this study adds The number of tablets in packets of paracetamol and salicylate preparations decreased markedly in the 12 months after the legislation The number of deaths from self poisoning with paracetamol alone and with salicylates alone decreased after the legislation There was also a decrease in the number of liver transplants and admissions to liver units with hepatic paracetamol poisoning and in the number of overdoses of paracetamol and salicylates in which large numbers of tablets were taken