Experts have criticised NHS advice that people self-isolating with Covid-19 should take ibuprofen, saying there is plausible evidence this could aggravate the condition.

The comments came after French authorities warned against taking widely used over the counter anti-inflammatory drugs. The country’s health minister, Olivier Véran, a qualified doctor and neurologist, tweeted on Saturday: “The taking of anti-inflammatories [ibuprofen, cortisone … ] could be a factor in aggravating the infection. In case of fever, take paracetamol. If you are already taking anti-inflammatory drugs, ask your doctor’s advice.”

NHS guidance states that people managing Covid-19 symptoms at home should take paracetamol or ibuprofen.

“I would advise against that,” said Prof Ian Jones, a virologist at the University of Reading. “There’s good scientific evidence for ibuprofen aggravating the condition or prolonging it. That recommendation needs to be updated.”

Paul Little, a professor of primary care research at the University of Southampton, said: “The general feeling is that the French advice is fairly sensible. There is now a sizeable literature from case control studies in several countries that prolonged illness or the complications of respiratory infections may be more common when non-steroidal anti-inflammatories [NSAIDs] are used.”

A trial by Little and his colleagues, published in the BMJ, found patients with respiratory infections such as coughs, colds and sore throats who were prescribed ibuprofen rather than paracetamol by their GP were more likely to subsequently suffer severe illness or complications. Several other studies have linked anti-inflammatory drugs to worsened pneumonia.

Little said this could be because inflammation is part of the body’s natural response to infection. “If you’re suppressing that natural response, you’re likely inhibiting your body’s ability to fight off infection,” he said.

The evidence in this area was “not 100% clear” and had not come directly from studies of patients with Covid-19, Little said. “I personally think that given there is plausible evidence for harm, the advice should be changed.

Should someone suffering from coronavirus with only ibuprofen in their bathroom cabinet grit their teeth and make do without? Little said despite the concerns, it would be reasonable to use ibuprofen as a last resort. For instance, if you were struggling to sleep, since getting enough rest is also important for recovery.

“If you’re desperate, particularly if you couldn’t get to sleep at night,then I’d take one,” he said. Otherwise, he recommended sweating it out or asking a friend or family member to post some paracetamol through the letterbox.

Charlotte Warren-Gash, an associate professor of epidemiology at the London School of Hygiene and Tropical Medicine, said: “For Covid-19, research is needed into the effects of specific NSAIDs among people with different underlying health conditions, which takes into account the severity of infection.

“In the meantime, for treating symptoms such as fever and sore throat, it seems sensible to stick to paracetamol as first choice.”

Public Health England said there was currently insufficient information on ibuprofen use and Covid-19 to advise people to stop using ibuprofen. “Currently there is no published scientific evidence that ibuprofen increases the risk of catching Covid-19 or makes the illness worse. There is also no conclusive evidence that taking ibuprofen is harmful for other respiratory infections,” it said in a statement.

“Most people with Covid-19 will have a mild illness and some people may need to take medicines, such as paracetamol or ibuprofen, to help with raised temperature, headache and other pains; always follow the instructions on the label if you do take these medicines and do not exceed the stated dose.

“Patients who have been prescribed NSAIDs for long-term health problems should continue to take them as directed by their healthcare professional,” the statement added.

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