Pharmacists must ensure patients are aware of the cardiovascular risks associated with diclofenac, experts have warned, after a study in the journal Plos Medicine found it was the most popular NSAID despite having the highest risk of side effects.

Diclofenac was the most commonly prescribed NSAID across 15 countries, including England, and had a market share of sales of nearly 30 per cent, according to the study published on Tuesday (February 12).

The drug also ranked highest of all NSAIDs studied for risks of heart attack or stroke, the researchers found after examining data from randomised trials and observational studies.

Diclofenac ranked highest of all painkillers for risks of heart attack or stroke	More on painkillers Nice: highlight dangers of frequent painkiller use Overcome fear of ibuprofen use in children MHRA: NSAID use should be as short as possible
	Diclofenac carried a similar risk to rofecoxib, an NSAID that was withdrawn from worldwide markets in 2004 because of its cardiovascular toxicity, they pointed out. And they called for diclofenac to be removed from the 74 national essential medicines lists that it appeared on across the world.

The most recent NHS figures show that, although there has been a slow decline in prescriptions of diclofenac in England since 2006, almost 5 million items were prescribed in 2011.

The significant use of diclofenac in England needed to be addressed by pharmacists, the Royal Pharmaceutical Society (RPS) told C+D.

"Pharmacists can assist patients by identifying cardiovascular risk factors where present, advising on suitable NSAID options based on their individual risk profile and liaising with the prescribing clinician where appropriate," said RPS spokesperson on cardiovascular medicines Helen Williams.

"Diclofenac, especially OTC, may be more appropriate for use by younger patients without known cardiovascular risk factors requiring short term NSAID courses: for example, following musculoskeletal injury," she added.

The British Heart Foundation (BHF) advised patients to discuss their concerns with their GP or pharmacist, who would help decide whether the benefits outweighed the risks.

"Anyone taking these painkillers should be aware of both their risks – especially of cardiovascular disease and internal bleeding – and benefits in treating debilitating pain such as that caused by arthritis," said BHF senior nurse Maureen Talbot.

The MHRA said it had already initiated a Europe-wide review of diclofenac, but for most patients the risks of side effects were outweighed by the benefits.

"Our advice remains that these medicines should be used for the shortest time necessary and at the lowest dose possible to control symptoms," an MHRA spokesperson said.

The study also found that naproxen, one of the safest NSAIDs, was one of the least popular. There were "strong reasons" for using these low-risk NSAIDs for patients at risk of cardiovascular disease, the researchers said.

Nice released guidance in September last year suggesting that pharmacists should warn patients that regularly using painkillers for a period of more than three months could cause "medication overuse headache".

Are your patients aware of the cardiovascular risks of diclofenac? Comment below or email us at [email protected] You can also find C+D on Twitter, LinkedIn and Facebook