Long-term high-dose use of painkillers such as ibuprofen or diclofenac is “equally hazardous” in terms of heart attack risk as use of the drug Vioxx, which was withdrawn due to its potential dangers, researchers said.

Presenting the results of a large international study into a class of painkillers called non-steroidal anti-inflammatory drugs (NSAIDs), the researchers said high doses of them increase the risk of a major vascular event -a heart attack, stroke or dying from cardiovascular disease by around a thirdm, Fox News Reported.

This means that for every 1,000 people with an average risk of heart disease who take high-dose diclofenac or ibuprofen for a year, about three extra would have an avoidable heart attack, of which one would be fatal, the researchers said.

This puts the heart risks of generic NSAIDs on a par with a newer class of NSAIDs known as COX-2 inhibitors or coxibs, which includes Vioxx a painkiller that U.S. drugmaker Merck pulled from sale in 2004 because of links to heart risks.

Other drugs in the coxib class include cerecoxib, sold by Pfizer under the brand name Celebrex, and etoricoxib, sold by Merck under the brand name Arcoxia.

“What we are saying is that they (coxibs, ibuprofen and diclofenac) have similar risks, but they also have similar benefits,” said Colin Baigent of the clinical trial service unit at Britain’s Oxford University, who led the study published in The Lancet medical journal.

He stressed that the risks are mainly relevant to people who suffer chronic pain, such as patients with arthritis who need to take high doses of painkillers such as 150mg of diclofenac or 2400mg of ibuprofen a day for long periods.

“A short course of lower dose tablets purchased without a prescription, for example, for a muscle sprain, is not likely to be hazardous,” he said.