Nearly 25 per cent of people who moved to a nursing home in Ontario were put on antipsychotic drugs within a year, according to a new study that raises questions about the practice.

Nursing home patients with dementia or Alzheimer's are sometimes given "neuroleptic" or antipsychotic drugs to control aggressive or agitated behaviour.

The medications were designed to treat schizophrenia and other major psychiatric illnesses. Doctors may prescribe them for dementia once other non-drug treatments have failed.

Dr. Paula Rochon

Researchers at the Institute for Clinical Evaluative Sciences in Toronto found many nursing home residents are given higher doses of antipsychotics than recommended, often without seeing a specialist.

"These therapies have been associated with problems like instability and falls and some problems like Parkinson-type symptoms," said Dr. Paula Rochon, a geriatrician in Toronto and the study's senior author.

Health Canada has also warned about a risk of stroke in seniors who take Zyprexa, which is in a new class of drugs called atypical antipsychotics.

The researchers examined data anonymous medical records from nearly 20,000 people aged 66 or older who entered a nursing home in Ontario between 1998 and 2000. They weren't prescribed antipsychotics before the move, and prescription patterns are expected to be the same across Canada.

In the May 4 issue of the Journal of the American Geriatrics Society, the researchers report:

• Antipsychotics were prescribed to 24 per cent of residents within one year of their admission to a nursing home.
• Almost 10 per cent of nursing home residents received an initial dose that exceeded recommendations.
• A geriatrician or psychiatrist saw only 14 per cent of residents in the 60 days before they received the antipsychotic prescription.

The researchers noted use of antipsychotics increased after atypical antipsychotics became available in the late 1990s, but the behavioral benefits of the new drugs haven't been shown conclusively.

In the U.S., legislation restricts when antipsychotics can be prescribed and at what dose.