Vioxx risks can occur within 2 weeks: Canada study

The risk of taking the painkiller Vioxx is more acute than previously thought, according to research published online Tuesday in the Canadian Medical Association Journal.

One quarter of patients who suffered a heart attack did so within the first 2 weeks of taking their first Vioxx prescription, a McGill University Health Center study revealed.

"The additional cardiovascular risk from Vioxx actually decreased with longer duration of use, suggesting that the period of highest susceptibility for most people taking Vioxx may occur earlier than previously believed," said Linda Levesque, the lead author of the study.

Merck & Co. Inc. pulled the $2.5 billion-a-year drug from the market in September 2004 after a study showed Vioxx doubled heart attack and stroke risk for patients who took it for 18 months or longer.

A Texas jury found last month that the painkiller caused the death of a 71-year-old man who had taken the drug for less than 1 month, and awarded his family damages of $32 million.

Merck faces about 10,000 Vioxx related lawsuits.

The Canadian study assessed the pattern of cardiovascular risk in seniors over a 3-year period to establish the timing of the Vioxx risk.