Scientists have warned older adults against regularly popping paracetamol due to links with alarming conditions like internal bleeding and chronic kidney disease.
A major analysis, by experts from the University of Nottingham, has found a ‘dose-dependent’ relationship between use of the painkiller and digestive, heart and kidney problems.
The study, which tracked the health of more than half a million over 65 year-olds over 20 years, revealed those prescribed paracetamol twice within six months are at a particularly high risk of complications.
When compared to a group of controls of the same age group, those with this number of prescriptions were more likely to suffer stomach ulcers, heart failure, hypertension and chronic kidney disease.
The more paracetamol a person used, the more they were also more likely to see a stomach ulcer bleed or split open.
The painkiller is often prescribed to older people to help them manage the symptoms of a range of chronic diseases such as arthritis and osteoporosis.
Studies suggest around 90 per cent of over 75 year-olds regularly take paracetamol, mostly to treat joint and bone pain, as well as the consequences of falls.
But the author of the new study, Professor Weiya Zhang, epidemiologist at the National Institute for Health and Care Research Biomedical Research Centre at the University of Nottingham, said patients should ‘carefully consider’ whether or not to take the medication often.
Paracetamol, known as acetaminophen in the US, is one of the most common drugs taken across the world.
‘The use of paracetamol as a first line pain killer for long-term conditions such as osteoarthritis in older people needs to be carefully considered,’ he said, adding that evidence shows it has a ‘minimal pain-relief effect’.
In 2022, health watchdog The National Institute For Health and Care Excellence changed its guidelines for treating osteoarthritis — the type of the disease that’s linked to age and develops when the protective cartilage on the ends of your bones breaks down, causing pain and mobility problems.
The updated rules state that GPs must offer exercise programmes as the first line treatment for the condition, and avoid ‘routinely’ offering paracetamol as it’s unlikely to be effective.
Anti-inflammatory creams can be used ‘alongside’ exercise, the guidance adds.
Paracetamol has long been thought to be gentler on the gut than non-steroidal anti-inflammatory painkillers such as ibuprofen.
However, some studies suggest that, in high doses, it can cause irritation to the upper gastrointestinal tract, resulting in symptoms like heartburn, pain, nausea and vomiting.
Previous research has shown that too much paracetamol can raise blood pressure. This chart shows the average blood pressure increase observed at various points among participants when they took a daily paracetamol dose of 4g of paracetamol.
Scientists are currently unsure as to why the medicine may cause kidney problems, however some studies have suggested it could interact with chemicals in the body to form toxins which damage the organ’s cells.
Experts have long warned about the impact of high doses of the painkiller on the liver.
Excess dosages of the drug — sold as Tylenol in the US — is considered to be the leading cause of acute liver failure in the Western world.
Too much overwhelms the liver’s normal pathway for metabolising the drug safely, and instead it ends up in a toxic form which damages the cells, eventually leading to liver failure.
One 2017 study found that the type of damage to the organ’s cells caused by paracetamol is similar to that induced by alcohol and hepatitis.
Meanwhile, other studies have found links between long term use of the painkiller and raised blood pressure.
This is thought to be due to the fact many patients take soluble versions of the medicine, which is high in sodium, increasing the risk of blood pressure spikes.
The maximum safe dose of paracetamol for adults is two 500mg tablets or capusles four times per day.
The NHS warns not to take more than eight tablets in a 24-hour period.
Experts have previously warned that it’s ‘too easy’ to overdose on the painkiller, as many people combined different products that contain paracetamol — such as those that treat cold and flu — and lose track of the dosage.
Dr Kenneth Simpson, liver disease specialist at Edinburgh University, previously told MailOnline that staggered overdoses can occur when people have pain and repeatedly take a little more paracetamol than they should.
He said: ‘They haven’t taken the sort of one-off massive overdoses taken by people who try to commit suicide, but over time the damage builds up and the effect can be fatal.
‘They are often taking paracetamol for pain and they don’t keep track of how much they’ve consumed over a few days.’
