There's growing evidence of a link between some common painkillers and heart attacks.
New research now reveals the extent of that risk, and says it can appear after just days.
Ibuprofen, naproxen, diclofenac, celecoxib and rofecoxib are from a group of medicines known as non-steroidal anti-inflammatory drugs (NSAIDs). They include household names like Nurofen and Voltaren.
New research, pooling four studies and analysing almost half a million patients, has now found NSAIDs increase the risk of a heart attack by 20 to 50 percent.
The risk starts in the first week and peaks in the first month.
But it has to be put into perspective - Auckland Professor of Cardiology Ralph Stewart says it's a relative risk.
"For the vast majority of people the risk of a heart attack is very small," he told Newshub.
People most at risk are those who already have heart disease and Prof Stewart says they should discuss the use of the medicines with their doctor.
"It is a reason, even though the risk is small, that you don't use them for no good reason," he said.
But Prof Stewart says you've got to weigh up the risk versus the benefit.
"For most, the risk doesn't outweigh the benefit of feeling better when you're in pain."
The risk also varies, depending on the drug, and how much you're taking. The higher the dose, the greater the risk.
The best advice is to take the lowest dose you can for the shortest time.