A Canadian study has shown that women are among several groups at increased risk of accidentally overdosing on acetaminophen, the common pain reliever found in Tylenol and other medications.
Acetaminophen overdose is the major cause of sudden liver failure in North America. The University of Calgary study examined risk factors and trends in hospitalization rates for overdoses in the Calgary area. Results showed that women, young people, aboriginals and socioeconomically disadvantaged groups are at increased risk.
The researchers also found that the rate of unintentional acetaminophen overdoses has been increasing since 2000, after declining between 1995 and 2000. But hospitalization rates for intentional acetaminophen overdoses have continued to decline steadily since 1995.
“The potential for unintentional overdosing is still a major problem in Canada,” says Dr. Abdel Aziz Shaheen, a hepatology research fellow at the University of Calgary.
Shaheen and his colleagues found that 1,543 patients were admitted for acetaminophen overdoses in the Calgary region (population one million) from 1995 to 2004. The majority of overdoses (85 per cent) were unintentional. Of these, 68 per cent were females with a median age of 26 years, seven per cent were aboriginals, 15 per cent received an insurance premium subsidy and 11 per cent received social assistance.
Women had more than twice the risk of acetaminophen overdose compared with men. The highest overall rates of acetaminophen overdosing were observed in the 10- to 19- and 20- to 29-year-old age groups.
“These findings highlight the necessity of preventive initiatives targeted at young age groups, females, aboriginals and socioeconomically disadvantaged groups,” Shaheen says.
For adults, the maximum recommended acetaminophen dose is 4,000 mg per day. Experts recommend checking labels carefully, because the ingredient is found in many over-the-counter and prescription medications.