MHRA reviews over-the-counter availability of diclofenac
UK drugs regulators have launched a consultation on whether diclofenac tablets should continue to be available over the counter, in light of the recent EU-wide decision to contraindicate their use in people with heart problems.
The European Medicines Agency recently ruled that systemic diclofenac should no longer be used by people with serious underlying heart or circulatory conditions, such as heart failure and heart disease, after concluding the risk of cardiovascular complications associated with its use outweigh the benefits.
The decision came after several studies highlighted the risk of cardiovascular disease (CVD) events with certain NSAIDs. Most recently, a study from the Medical Research Council showed risk increases with diclofenac and high-dose ibuprofen were similar to those for selective COX-2 inhibitors, while naproxen was risk neutral.
Now the UK Medicines and Healthcare Regulatory Agency (MHRA) has announced it will consult doctors and other healthcare professionals on whether oral preparations of diclofenac should stop being classed as pharmacy medicines, or whether they should just have stronger product information warnings and fewer listed indications.
MHRA experts said pharmacists may find it difficult to identify people with high cardiovascular risk. In addition, diclofenac currently has wide-ranging indications, including for colds and flu, and there is a risk of diclofenac and other NSAIDs being used together.
Dr Tom Margham, primary care lead for Arthritis Research UK and a GP in East London, told Pulse: ‘Following recent research into the link between diclofenac and heart disease, now is the right time to review its over-the-counter use.
‘However, as diclofenac is only available from qualified community pharmacists, in low doses, for a restricted number of days, the risk of heart disease and associated complications remains relatively low.’
Dr Patricia McGettigan, a clinical pharmacologist at Barts and The London School of Medicine and Dentistry, who previously called for diclofenac to be withdrawn from essential medicines lists, said over-the-counter availability of diclofenac was of ‘real concern’, especially for people at high baseline risk.
Dr McGettigan said: ‘There are many people in the community whose annual risk of a CVD event is of the order of 5%. For these individuals, the overall 40% risk increase associated with diclofenac use gives rise to an excess of 20 events per 1,000 users per year, and higher if high doses are taken.
‘In the face of these sorts of excess event numbers and when there are safer NSAIDs available, making diclofenac available for self-selection over-the-counter use, even with pharmacist supervision, is very unwise. It should be prescription-only.’
Dr McGettigan also questioned whether diclofenac use is relatively safe when used short-term, noting that one study has shown the risk with diclofenac is elevated from when the treatment is started.
Dr John Dickson, founder of the Primary Care Rheumatology Society and community rheumatologist, said he would like diclofenac removed from sale over-the-counter.
He said: ‘The problem with diclofenac is that it doesn’t have a wide range of doses – 150 mg is the top dose and you can take 25 mg three times a day, so you’re into the highest doses quite quickly. People may well take one if not two more than they should, and so may overdose quite easily.
‘The other thing is it has liver side-effects – the National Prescribing Centre questioned whether it should be prescribed even. You then have the problem that if you take paracetamol as well, it may be particularly toxic to the liver.
‘Really it’s not a good one to have over-the-counter, so I would be quite happy for them to remove it again.’