MONDAY, Aug. 25 (HealthDay News) -- Safety warnings slowed the use of antipsychotic drugs in seniors with dementia. But the overall use of the drugs in the elderly increased, a finding which suggests that warnings may not be sufficient to protect patients, Canadian researchers say.

Between late 2002 and June 2005, Health Canada issued three warnings that three new atypical antipsychotic drugs increased the risk of stroke and death in elderly patients with dementia.

The researchers analyzed prescription drug data in the province of Ontario and found that antipsychotic drug use among the elderly increased 20 percent from the month prior to the first warning in September 2002 to February 2007. About 70 percent of the seniors receiving antipsychotic drugs lived in nursing homes, and about 40 percent of them were 85 or older.

"This finding highlights the limited impact of warnings and suggests that more effective approaches are needed to protect vulnerable populations from potentially hazardous medications," wrote Dr. Geoffrey Anderson, of the University of Toronto, and colleagues.

The study was published in the Canadian Medical Association Journal.

Some health care warnings don't have much effect, because the warnings don't provide doctors with information about the safety and effectiveness of alternative treatments, Dr. Laurence Katz, of the University of Manitoba, wrote in an accompanying comment article.

More information

The Annals of Internal Medicine has more about antipsychotic drug use in seniors with dementia.