Restricting paracetamol in the United Kingdom to reduce poisoning: a systematic review.

BACKGROUND Paracetamol poisoning is implicated in about 150-200 poisoning deaths per year in England and Wales. We review previous studies assessing the effectiveness of regulations introduced in 1998 to restrict sales of paracetamol and reduce paracetamol poisoning. METHODS We searched the following electronic databases: MEDLINE, EMBASE, CINHAL, HIMIC, COCH, APC, CENTRAL and DARE. English language publications between 1998 and 2003 were included. Studies were included if they took place in the United Kingdom and assessed changes in any aspect of paracetamol poisoning following the introduction of the 1998 regulations. RESULTS Twelve studies were identified, which examined several different outcomes. Three studies examined admissions to liver transplant units; all reported reductions. Eight studies evaluated severity of paracetamol poisoning; three reported reductions but five did not. Five out of six studies reported reductions in hospital admissions. One study reported reduced mortality in England and Wales after 1 year while another found no difference in Scotland 2 years after the regulations were introduced. Two studies observed a significant reduction in over-the-counter sales. Studies suffered from several limitations including short follow-up periods, no case definition for paracetamol poisoning and lack of comparison groups. CONCLUSIONS The limitations of these studies makes it difficult to draw firm conclusions. They do, however, suggest that the 1998 regulations may have been associated with reduced admissions to liver units and liver transplants, reduced hospital attendance due to paracetamol poisoning and reduced sales of paracetamol. Further research is needed to fully evaluate the impact of the 1998 regulations. In the future, formal evaluation of the impact of similar interventions should be an integral part of policy formation.