Voltaren's active ingredient, dicolfenac has been the topic of alarm in a study in the journal of the American Medical Association.
On surveying results for 1.5 million people using this anti-inflammatory drug it was found to increase the relative risk of heart attack and stroke by up to 40%.
Newcastle University spokesperson David Henry said, "We've looked at the effects of causing heart failure, we've also looked at the propensity of dicolfenac to damage liver, and now we're looking at the propensity to cause heart attacks. So from that simple list you realize that they have a lot of side effects."
The researchers have advised those already at risk of heart attack to consider alternative treatments.