Over the past two decades, taking drugs to treat depression has become a national pastime in Canada, and the trend is likely to continue, a new study says.

Three University of Toronto researchers analyzed prescription habits in Canada between 1981 and 2000.

During that period, the total number of prescriptions for antidepressants jumped to 14.5 million a year from 3.2 million.

This 353-per-cent increase occurred while the Canadian population increased 1 per cent annually.

The total amount of money spent yearly on antidepressant drugs grew to $543.4-million in 2000 from $31.4-million in 1981. The average cost of a prescription, excluding pharmacists' fees, rose to $37.44 from $9.85.

Part of the reason for bigger bills is the fact that many of the drugs were approved during the period studied, and drug companies are still seeking to recover the estimated $400-million to $500-million cost for development and approval.

If the trend continues, Canadians will be spending $1.2-billion on drugs by 2005 to kick-start themselves out of a clinical case of the blues, say the authors of the paper, which appears in the Annals of Pharmacotherapy.

The precise reason for the increase in drug-taking for depression is murky.

Part of the cause may be that depression became more topical as new and safer drugs have been developed.

"During the time Prozac was first introduced, people used to talk about it being Vitamin P, so clearly there was the impression that everyone and their neighbours were using them," said Gideon Koren, a professor of pharmacology at the University of Toronto and one of the study's authors. Use also went up because the new drugs lack the side effects -- seizures and heart attacks among them -- that discouraged doctors from prescribing and patients from taking older drugs.

While an estimated 4.3 per cent of Canadians are clinically depressed, the number of people being treated has likely increased because of:

Changes in the diagnosis of depression to include bulimia, severe panic attacks, obsessive-compulsive disorders and others;

New calibrations of the length of bouts of depression;

The prescribing of medications after symptoms have disappeared to ward off future episodes;

A decline in the number of patients undergoing psychotherapy.

A greater willingness on the part of people to admit they are clinically depressed.

This may also help explain the dramatic increase that has been discovered in the number of children and adolescents diagnosed with depression.
Gloomy news
According to researchers at U of % and the Hospital for Sick Children, the use of antidepressants by Canadians has soared by more than 300 per cent over the past two decades.
COST PER PRESCRIPTION

1981        $9.85


2000       $37.44


Expenditures on antidepressants in 1981:   $31.4-million


Expenditures on antidepressants in 2000:  $543.4-million