Unsafe drugs linger on market

Dangerous drugs often stay on the market in Canada for more than three years before eventually being pulled from drugstore shelves, new Canadian research shows.

The study, by Dr. Joel Lexchin, an emergency physician and York University professor of health policy, found that about four per cent of new drugs approved by Health Canada between January 1990 and December 2009 were eventually withdrawn for safety reasons.

The median time between approval and withdrawal was 1,271 days.

Some drugs received a serious safety warning within 20 days of being approved.

“How is it that you need to issue a serious safety warning within two to three weeks of the drug coming on the market?” Lexchin asked. “What does that say about how well the safety data was scrutinized before the drugs were approved?”

For his study, published this week in the journal Open Medicine, Lexchin compiled a list of all drugs approved between 1990 and 2009 and subsequently withdrawn as of October 2013. The date of approval, the date the first serious safety warning was issued (if one was issued) and the date of withdrawal from the market were recorded for each drug.

Of the 528 new drugs approved during the period, 22 were eventually withdrawn. Eleven had been the subject of a safety warning, and 11 had not.