Ibuprofen is more dangerous than people realise and shouldn't be sold at supermarkets, researchers have claimed.
Sold over-the-counter under brand names such as Nurofen and Maxigesic, ibuprofen has been linked to an increased risk of cardiac arrest in a new Dutch study.
People using ibuprofen were 31 percent more likely to suffer cardiac arrest in the following month, according to research published in European Heart Journal - Cardiovascular Pharmacotherapy.
It belongs to a group of painkillers called NSAIDs, short for non-steroidal anti-inflammatory drugs.
"The current message being sent to the public about NSAIDs is wrong," said lead researcher Prof Gunnar Gislason, professor of cardiology at Copenhagen University Hospital.
"If you can buy these drugs in a convenience store then you probably think 'they must be safe for me'. Our study… confirms that they should be taken seriously, and used only after consulting a healthcare professional."
Ibuprofen wasn't the worst commonly used painkiller though - diclofenac, commonly known as Voltaren, was linked to a 50 percent increase.
"Diclofenac is the riskiest NSAID and should be avoided by patients with cardiovascular disease and the general population," says Prof Gislason.
"Safer drugs are available that have similar painkilling effects, so there is no reason to use diclofenac."
Researchers used data collected over a nine-year period, covering nearly 29,000 patients. Ibuprofen made up half of all NSAID use, with diclofenac second, making up 22 percent.
NSAIDs' effects on the body that could result in cardiac arrests include blood clots, artery constriction, fluid retention and raised blood pressure.
"I don't think these drugs should be sold in supermarkets or petrol stations where there is no professional advice on how to use them," says Prof Gislason.
"Over-the-counter NSAIDs should only be available at pharmacies, in limited quantities, and in low doses."
Despite their popularity, both ibuprofen and diclofenac proved a greater risk than naproxen, celecoxib and rofecoxib. The study notes however the lack of link between those three drugs and cardiac arrest could be down to their minimal usage.
Dicloefenac, naproxen and celecoxib are only available in New Zealand with a prescription.
Rofecoxib was withdrawn in 2004 by pharmaceutical giant Merck over concerns about increased risk of heart attacks and strokes. Health experts later cleared it for sale, but Merck didn't resume manufacture.
Nurofen said its packaging carries a warning about cardiac risk.